---
_id: '17543'
abstract:
- lang: eng
text: 'Massive black-hole (MBH) binaries, which are expected to form following the
merger of their parent galaxies, produce gravitational waves which will be detectable
by Pulsar Timing Arrays at nanohertz frequencies (year periods). While no confirmed,
compact MBH binary systems have been seen in electromagnetic observations, a large
number of candidates have recently been identified in optical surveys of AGN variability.
Using a combination of cosmological, hydrodynamic simulations; comprehensive,
semi-analytic binary merger models; and analytic AGN spectra and variability prescriptions;
we calculate the expected electromagnetic detection rates of MBH binaries as periodically
variable AGN. In particular, we consider two independent variability models: (i)
Doppler boosting due to large orbital velocities, and (ii) hydrodynamic variability
in which the fueling of MBH accretion disks is periodically modulated by the companion.
Our models predict that numerous MBH binaries should be present and distinguishable
in the existing data. In particular, our fiducial models produce an expectation
value of 0.2 (Doppler) and 5 (hydrodynamic) binaries to be identifiable in CRTS,
while 20 and 100 are expected after five years of LSST observations. The brightness
variations in most systems are too small to be distinguishable, but almost 1%
of AGN at redshifts z≲0.6 could be in massive binaries. We analyze the predicted
binary parameters of observable systems and their selection biases, and include
an extensive discussion of our model parameters and uncertainties.'
article_processing_charge: No
article_type: original
author:
- first_name: Luke Zoltan
full_name: Kelley, Luke Zoltan
last_name: Kelley
- first_name: Zoltán
full_name: Haiman, Zoltán
id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
last_name: Haiman
- first_name: Alberto
full_name: Sesana, Alberto
last_name: Sesana
- first_name: Lars
full_name: Hernquist, Lars
last_name: Hernquist
citation:
ama: Kelley LZ, Haiman Z, Sesana A, Hernquist L. Massive BH binaries as periodically
variable AGN. Monthly Notices of the Royal Astronomical Society. 2019;485(2):1579-1594.
doi:10.1093/mnras/stz150
apa: Kelley, L. Z., Haiman, Z., Sesana, A., & Hernquist, L. (2019). Massive
BH binaries as periodically variable AGN. Monthly Notices of the Royal Astronomical
Society. Oxford University Press. https://doi.org/10.1093/mnras/stz150
chicago: Kelley, Luke Zoltan, Zoltán Haiman, Alberto Sesana, and Lars Hernquist.
“Massive BH Binaries as Periodically Variable AGN.” Monthly Notices of the
Royal Astronomical Society. Oxford University Press, 2019. https://doi.org/10.1093/mnras/stz150.
ieee: L. Z. Kelley, Z. Haiman, A. Sesana, and L. Hernquist, “Massive BH binaries
as periodically variable AGN,” Monthly Notices of the Royal Astronomical Society,
vol. 485, no. 2. Oxford University Press, pp. 1579–1594, 2019.
ista: Kelley LZ, Haiman Z, Sesana A, Hernquist L. 2019. Massive BH binaries as periodically
variable AGN. Monthly Notices of the Royal Astronomical Society. 485(2), 1579–1594.
mla: Kelley, Luke Zoltan, et al. “Massive BH Binaries as Periodically Variable AGN.”
Monthly Notices of the Royal Astronomical Society, vol. 485, no. 2, Oxford
University Press, 2019, pp. 1579–94, doi:10.1093/mnras/stz150.
short: L.Z. Kelley, Z. Haiman, A. Sesana, L. Hernquist, Monthly Notices of the Royal
Astronomical Society 485 (2019) 1579–1594.
date_created: 2024-09-05T09:59:54Z
date_published: 2019-01-30T00:00:00Z
date_updated: 2024-09-18T08:52:07Z
day: '30'
doi: 10.1093/mnras/stz150
extern: '1'
fulldoi: https://doi.org/10.1093/mnras/stz150
intvolume: ' 485'
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1093/mnras/stz150
month: '01'
oa: 1
oa_version: Published Version
page: 1579-1594
publication: Monthly Notices of the Royal Astronomical Society
publication_identifier:
issn:
- 0035-8711
- 1365-2966
publication_status: published
publisher: Oxford University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Massive BH binaries as periodically variable AGN
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 485
year: '2019'
...
---
_id: '17556'
abstract:
- lang: eng
text: The abundance of molecular hydrogen (H2), the primary coolant in primordial
gas, is critical for the thermodynamic evolution and star-formation histories
in early protogalaxies. Determining the photodissociation rate of H2 by an incident
Lyman-Werner (LW) flux is thus crucial, but prohibitively expensive to calculate
on the fly in simulations. The rate is sensitive to the H2 rovibrational distribution,
which in turn depends on the gas density, temperature, and incident LW radiation
field. We use the publicly available cloudy package to model primordial gas clouds
and compare exact photodissociation rate calculations to commonly-used fitting
formulae. We find the fit from Wolcott-Green et al. (2011) is most accurate for
moderate densities n~10^3 cm^{-3} and temperatures, T~10^3K, and we provide a
new fit, which captures the increase in the rate at higher densities and temperatures,
owing to the increased excited rovibrational populations in this regime. Our new
fit has typical errors of a few percent percent up to n =<10^7 cm^{-3}, T =< 8000K,
and H2 column density NH2 =<10^{17} cm^{-2}, and can be easily utilized in simulations.
We also show that pumping of the excited rovibrational states of H2 by a strong
LW flux further modifies the level populations when the gas density is low, and
noticeably decreases self-shielding for J_21 > 10^3 and n < 10^2 cm^{-3}. This
may lower the "critical flux" at which primordial gas remains H2-poor in some
protogalaxies, enabling massive black hole seed formation.
article_processing_charge: No
article_type: original
author:
- first_name: J
full_name: Wolcott-Green, J
last_name: Wolcott-Green
- first_name: Zoltán
full_name: Haiman, Zoltán
id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
last_name: Haiman
citation:
ama: 'Wolcott-Green J, Haiman Z. H2 self-shielding with non-LTE rovibrational populations:
Implications for cooling in protogalaxies. Monthly Notices of the Royal Astronomical
Society. 2019;484(2):2467-2473. doi:10.1093/mnras/sty3280'
apa: 'Wolcott-Green, J., & Haiman, Z. (2019). H2 self-shielding with non-LTE
rovibrational populations: Implications for cooling in protogalaxies. Monthly
Notices of the Royal Astronomical Society. Oxford University Press. https://doi.org/10.1093/mnras/sty3280'
chicago: 'Wolcott-Green, J, and Zoltán Haiman. “H2 Self-Shielding with Non-LTE Rovibrational
Populations: Implications for Cooling in Protogalaxies.” Monthly Notices of
the Royal Astronomical Society. Oxford University Press, 2019. https://doi.org/10.1093/mnras/sty3280.'
ieee: 'J. Wolcott-Green and Z. Haiman, “H2 self-shielding with non-LTE rovibrational
populations: Implications for cooling in protogalaxies,” Monthly Notices of
the Royal Astronomical Society, vol. 484, no. 2. Oxford University Press,
pp. 2467–2473, 2019.'
ista: 'Wolcott-Green J, Haiman Z. 2019. H2 self-shielding with non-LTE rovibrational
populations: Implications for cooling in protogalaxies. Monthly Notices of the
Royal Astronomical Society. 484(2), 2467–2473.'
mla: 'Wolcott-Green, J., and Zoltán Haiman. “H2 Self-Shielding with Non-LTE Rovibrational
Populations: Implications for Cooling in Protogalaxies.” Monthly Notices of
the Royal Astronomical Society, vol. 484, no. 2, Oxford University Press,
2019, pp. 2467–73, doi:10.1093/mnras/sty3280.'
short: J. Wolcott-Green, Z. Haiman, Monthly Notices of the Royal Astronomical Society
484 (2019) 2467–2473.
date_created: 2024-09-05T10:24:40Z
date_published: 2019-01-16T00:00:00Z
date_updated: 2024-09-18T12:00:29Z
day: '16'
doi: 10.1093/mnras/sty3280
extern: '1'
fulldoi: https://doi.org/10.1093/mnras/sty3280
intvolume: ' 484'
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1093/mnras/sty3280
month: '01'
oa: 1
oa_version: Published Version
page: 2467-2473
publication: Monthly Notices of the Royal Astronomical Society
publication_identifier:
issn:
- 0035-8711
- 1365-2966
publication_status: published
publisher: Oxford University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'H2 self-shielding with non-LTE rovibrational populations: Implications for
cooling in protogalaxies'
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 484
year: '2019'
...
---
_id: '17565'
abstract:
- lang: eng
text: 'The coalescence of a compact object with a 104−107M⊙ supermassive black hole
(SMBH) produces mHz gravitational waves (GWs) detectable by the future Laser Interferometer
Space Antenna (LISA). If such an inspiral occurs in the accretion disc of an active
galactic nucleus (AGN), the gas torques imprint a small deviation in the GW waveform.
Here we present two-dimensional hydrodynamical simulations with the moving-mesh
code DISCO of a BH inspiraling at the GW rate in a binary system with a mass ratio
q=M2/M1=10−3, embedded in an accretion disc. We assume a locally isothermal equation
of state for the gas (with Mach number M=20) and implement a standard α-prescription
for its viscosity (with α=0.03). We find disc torques on the binary that are weaker
than in previous semi-analytic toy models, and are in the opposite direction:
the gas disc slows down, rather than speeds up the inspiral. We compute the resulting
deviations in the GW waveform, which scale linearly with the mass of the disc.
The SNR of these deviations accumulates mostly at high frequencies, and becomes
detectable in a 5-year LISA observation if the total phase shift exceeds a few
radians. We find that this occurs if the disc surface density exceeds Σ0≳102−3gcm−2,
as may be the case in thin discs with near-Eddington accretion rates. Since the
characteristic imprint on the GW signal is strongly dependent on disc parameters,
a LISA detection of an intermediate mass ratio inspiral would probe the physics
of AGN discs and migration.'
article_processing_charge: No
article_type: original
author:
- first_name: A M
full_name: Derdzinski, A M
last_name: Derdzinski
- first_name: D
full_name: D’Orazio, D
last_name: D’Orazio
- first_name: P
full_name: Duffell, P
last_name: Duffell
- first_name: Zoltán
full_name: Haiman, Zoltán
id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
last_name: Haiman
- first_name: A
full_name: MacFadyen, A
last_name: MacFadyen
citation:
ama: 'Derdzinski AM, D’Orazio D, Duffell P, Haiman Z, MacFadyen A. Probing gas disc
physics with LISA: simulations of an intermediate mass ratio inspiral in an accretion
disc. Monthly Notices of the Royal Astronomical Society. 2019;486(2):2754-2765.
doi:10.1093/mnras/stz1026'
apa: 'Derdzinski, A. M., D’Orazio, D., Duffell, P., Haiman, Z., & MacFadyen,
A. (2019). Probing gas disc physics with LISA: simulations of an intermediate
mass ratio inspiral in an accretion disc. Monthly Notices of the Royal Astronomical
Society. Oxford University Press. https://doi.org/10.1093/mnras/stz1026'
chicago: 'Derdzinski, A M, D D’Orazio, P Duffell, Zoltán Haiman, and A MacFadyen.
“Probing Gas Disc Physics with LISA: Simulations of an Intermediate Mass Ratio
Inspiral in an Accretion Disc.” Monthly Notices of the Royal Astronomical Society.
Oxford University Press, 2019. https://doi.org/10.1093/mnras/stz1026.'
ieee: 'A. M. Derdzinski, D. D’Orazio, P. Duffell, Z. Haiman, and A. MacFadyen, “Probing
gas disc physics with LISA: simulations of an intermediate mass ratio inspiral
in an accretion disc,” Monthly Notices of the Royal Astronomical Society,
vol. 486, no. 2. Oxford University Press, pp. 2754–2765, 2019.'
ista: 'Derdzinski AM, D’Orazio D, Duffell P, Haiman Z, MacFadyen A. 2019. Probing
gas disc physics with LISA: simulations of an intermediate mass ratio inspiral
in an accretion disc. Monthly Notices of the Royal Astronomical Society. 486(2),
2754–2765.'
mla: 'Derdzinski, A. M., et al. “Probing Gas Disc Physics with LISA: Simulations
of an Intermediate Mass Ratio Inspiral in an Accretion Disc.” Monthly Notices
of the Royal Astronomical Society, vol. 486, no. 2, Oxford University Press,
2019, pp. 2754–65, doi:10.1093/mnras/stz1026.'
short: A.M. Derdzinski, D. D’Orazio, P. Duffell, Z. Haiman, A. MacFadyen, Monthly
Notices of the Royal Astronomical Society 486 (2019) 2754–2765.
date_created: 2024-09-05T12:05:43Z
date_published: 2019-09-05T00:00:00Z
date_updated: 2024-09-18T11:01:36Z
day: '05'
doi: 10.1093/mnras/stz1026
extern: '1'
fulldoi: https://doi.org/10.1093/mnras/stz1026
intvolume: ' 486'
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1093/mnras/stz1026
month: '09'
oa: 1
oa_version: Published Version
page: 2754-2765
publication: Monthly Notices of the Royal Astronomical Society
publication_identifier:
issn:
- 0035-8711
- 1365-2966
publication_status: published
publisher: Oxford University Press
quality_controlled: '1'
related_material:
link:
- relation: erratum
url: https://doi.org/10.1093/mnras/stz2435
scopus_import: '1'
status: public
title: 'Probing gas disc physics with LISA: simulations of an intermediate mass ratio
inspiral in an accretion disc'
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 486
year: '2019'
...
---
_id: '17567'
abstract:
- lang: eng
text: The growing number of stellar-mass binary black hole mergers discovered by
Advanced LIGO and Advanced Virgo are starting to constrain the binaries' origin
and environment. However, we still lack sufficiently accurate modeling of binary
formation channels to obtain strong constraints, or to identify sub-populations.
One promising formation mechanism that could result in different black hole properties
is binaries merging within the accretion disks of Active Galactic Nuclei (AGN).
Here we show that the black holes' orbital alignment with the AGN disks preferentially
selects heavier black holes. We carry out Monte Carlo simulations of orbital alignment
with AGN disks, and find that AGNs harden the initial black hole mass function.
Assuming an initial power law mass distribution M−βbh, we find that the power
law index changes by Δβ∼1.3, resulting in a more top-heavy population of merging
black holes. This change is independent of the mass of, and accretion rate onto,
the supermassive black hole in the center of the AGN. Our simulations predict
an AGN-assisted merger rate of ∼4Gpc−3yr−1. With its hardened mass spectra, the
AGN channel could be responsible for 10−50% of gravitational-wave detections.
article_number: '122'
article_processing_charge: No
article_type: original
author:
- first_name: Y.
full_name: Yang, Y.
last_name: Yang
- first_name: I.
full_name: Bartos, I.
last_name: Bartos
- first_name: Zoltán
full_name: Haiman, Zoltán
id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
last_name: Haiman
- first_name: B.
full_name: Kocsis, B.
last_name: Kocsis
- first_name: Z.
full_name: Márka, Z.
last_name: Márka
- first_name: N. C.
full_name: Stone, N. C.
last_name: Stone
- first_name: S.
full_name: Márka, S.
last_name: Márka
citation:
ama: Yang Y, Bartos I, Haiman Z, et al. AGN disks harden the mass distribution of
stellar-mass binary black hole mergers. The Astrophysical Journal. 2019;876(2).
doi:10.3847/1538-4357/ab16e3
apa: Yang, Y., Bartos, I., Haiman, Z., Kocsis, B., Márka, Z., Stone, N. C., &
Márka, S. (2019). AGN disks harden the mass distribution of stellar-mass binary
black hole mergers. The Astrophysical Journal. American Astronomical Society.
https://doi.org/10.3847/1538-4357/ab16e3
chicago: Yang, Y., I. Bartos, Zoltán Haiman, B. Kocsis, Z. Márka, N. C. Stone, and
S. Márka. “AGN Disks Harden the Mass Distribution of Stellar-Mass Binary Black
Hole Mergers.” The Astrophysical Journal. American Astronomical Society,
2019. https://doi.org/10.3847/1538-4357/ab16e3.
ieee: Y. Yang et al., “AGN disks harden the mass distribution of stellar-mass
binary black hole mergers,” The Astrophysical Journal, vol. 876, no. 2.
American Astronomical Society, 2019.
ista: Yang Y, Bartos I, Haiman Z, Kocsis B, Márka Z, Stone NC, Márka S. 2019. AGN
disks harden the mass distribution of stellar-mass binary black hole mergers.
The Astrophysical Journal. 876(2), 122.
mla: Yang, Y., et al. “AGN Disks Harden the Mass Distribution of Stellar-Mass Binary
Black Hole Mergers.” The Astrophysical Journal, vol. 876, no. 2, 122, American
Astronomical Society, 2019, doi:10.3847/1538-4357/ab16e3.
short: Y. Yang, I. Bartos, Z. Haiman, B. Kocsis, Z. Márka, N.C. Stone, S. Márka,
The Astrophysical Journal 876 (2019).
date_created: 2024-09-05T12:11:39Z
date_published: 2019-05-10T00:00:00Z
date_updated: 2024-09-18T13:26:34Z
day: '10'
doi: 10.3847/1538-4357/ab16e3
extern: '1'
fulldoi: https://doi.org/10.3847/1538-4357/ab16e3
intvolume: ' 876'
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.3847/1538-4357/ab16e3
month: '05'
oa: 1
oa_version: Published Version
publication: The Astrophysical Journal
publication_identifier:
issn:
- 0004-637X
- 1538-4357
publication_status: published
publisher: American Astronomical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: AGN disks harden the mass distribution of stellar-mass binary black hole mergers
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 876
year: '2019'
...
---
_id: '17603'
abstract:
- lang: eng
text: Weak gravitational lensing is one of the most promising cosmological probes
of the late universe. Several large ongoing (DES, KiDS, HSC) and planned (LSST,
Euclid, WFIRST) astronomical surveys attempt to collect even deeper and larger
scale data on weak lensing. Due to gravitational collapse, the distribution of
dark matter is non-Gaussian on small scales. However, observations are typically
evaluated through the two-point correlation function of galaxy shear, which does
not capture non-Gaussian features of the lensing maps. Previous studies attempted
to extract non-Gaussian information from weak lensing observations through several
higher order statistics such as the three-point correlation function, peak counts,
or Minkowski functionals. Deep convolutional neural networks (CNN) emerged in
the field of computer vision with tremendous success, and they offer a new and
very promising framework to extract information from 2D or 3D astronomical data
sets, confirmed by recent studies on weak lensing. We show that a CNN is able
to yield significantly stricter constraints of (σ8, Ωm) cosmological parameters
than the power spectrum using convergence maps generated by full N-body simulations
and ray-tracing, at angular scales and shape noise levels relevant for future
observations. In a scenario mimicking LSST or Euclid, the CNN yields 2.4–2.8 times
smaller credible contours than the power spectrum, and 3.5–4.2 times smaller at
noise levels corresponding to a deep space survey such as WFIRST. We also show
that at shape noise levels achievable in future space surveys the CNN yields 1.4–2.1 times
smaller contours than peak counts, a higher order statistic capable of extracting
non-Gaussian information from weak lensing maps.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Dezső
full_name: Ribli, Dezső
last_name: Ribli
- first_name: Bálint Ármin
full_name: Pataki, Bálint Ármin
last_name: Pataki
- first_name: José Manuel
full_name: Zorrilla Matilla, José Manuel
last_name: Zorrilla Matilla
- first_name: Daniel
full_name: Hsu, Daniel
last_name: Hsu
- first_name: Zoltán
full_name: Haiman, Zoltán
id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
last_name: Haiman
- first_name: István
full_name: Csabai, István
last_name: Csabai
citation:
ama: Ribli D, Pataki BÁ, Zorrilla Matilla JM, Hsu D, Haiman Z, Csabai I. Weak lensing
cosmology with convolutional neural networks on noisy data. Monthly Notices
of the Royal Astronomical Society. 2019;490(2):1843-1860. doi:10.1093/mnras/stz2610
apa: Ribli, D., Pataki, B. Á., Zorrilla Matilla, J. M., Hsu, D., Haiman, Z., &
Csabai, I. (2019). Weak lensing cosmology with convolutional neural networks on
noisy data. Monthly Notices of the Royal Astronomical Society. Oxford University
Press. https://doi.org/10.1093/mnras/stz2610
chicago: Ribli, Dezső, Bálint Ármin Pataki, José Manuel Zorrilla Matilla, Daniel
Hsu, Zoltán Haiman, and István Csabai. “Weak Lensing Cosmology with Convolutional
Neural Networks on Noisy Data.” Monthly Notices of the Royal Astronomical Society.
Oxford University Press, 2019. https://doi.org/10.1093/mnras/stz2610.
ieee: D. Ribli, B. Á. Pataki, J. M. Zorrilla Matilla, D. Hsu, Z. Haiman, and I.
Csabai, “Weak lensing cosmology with convolutional neural networks on noisy data,”
Monthly Notices of the Royal Astronomical Society, vol. 490, no. 2. Oxford
University Press, pp. 1843–1860, 2019.
ista: Ribli D, Pataki BÁ, Zorrilla Matilla JM, Hsu D, Haiman Z, Csabai I. 2019.
Weak lensing cosmology with convolutional neural networks on noisy data. Monthly
Notices of the Royal Astronomical Society. 490(2), 1843–1860.
mla: Ribli, Dezső, et al. “Weak Lensing Cosmology with Convolutional Neural Networks
on Noisy Data.” Monthly Notices of the Royal Astronomical Society, vol.
490, no. 2, Oxford University Press, 2019, pp. 1843–60, doi:10.1093/mnras/stz2610.
short: D. Ribli, B.Á. Pataki, J.M. Zorrilla Matilla, D. Hsu, Z. Haiman, I. Csabai,
Monthly Notices of the Royal Astronomical Society 490 (2019) 1843–1860.
date_created: 2024-09-05T13:11:16Z
date_published: 2019-09-17T00:00:00Z
date_updated: 2024-09-23T13:50:39Z
day: '17'
doi: 10.1093/mnras/stz2610
extern: '1'
external_id:
arxiv:
- '1902.03663'
fulldoi: https://doi.org/10.1093/mnras/stz2610
intvolume: ' 490'
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: ' https://doi.org/10.48550/arXiv.1902.03663'
month: '09'
oa: 1
oa_version: Preprint
page: 1843-1860
publication: Monthly Notices of the Royal Astronomical Society
publication_identifier:
issn:
- 0035-8711
- 1365-2966
publication_status: published
publisher: Oxford University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Weak lensing cosmology with convolutional neural networks on noisy data
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 490
year: '2019'
...
---
OA_type: closed access
_id: '17915'
abstract:
- lang: eng
text: The construction of self-assembled iron phthalocyanine (FePc) systems on gold
electrodes modified by self-assembled monolayers (SAMs) is becoming an interesting
strategy for obtaining electrocatalytic molecular building blocks for the oxygen
reduction reaction (ORR). In this work, we have measured the conductance of pyridiniums
axial ligands at the single molecule level using the scanning tunneling microscope-based
break-junction method (STM-Break Junction) to study the role of the axial ligand
on the activity of the self-assembled FePc systems on a gold electrode surface.
The electron-pulling effect of pyridinium axial ligands is known to increase the
electrocatalytic activity of FePc for the oxygen reduction reaction (ORR). We
have used these systems as a platform for carrying out a comparative study for
understanding the real influence of the proximal axial ligands. Further, these
ligands act as molecular wires between the gold electrode surface and the FePc
molecule. The pyridinium molecules were synthesized following a series of structural
variations using a basic molecular backbone. From conductance measurements obtained
for each pyridinium molecule, it was possible to establish that electron transport
through each pyridinium does not influence the activity of FePc for ORR in alkaline
media. In addition, the DFT calculations shows that the axial ligand in FePc modifies
its catalytic activity by decreasing the binding energy of O2 to the Fe site.
article_number: '134996'
article_processing_charge: No
article_type: original
author:
- first_name: Cristian
full_name: Gutiérrez-Ceron, Cristian
last_name: Gutiérrez-Ceron
- first_name: Rubén
full_name: Oñate, Rubén
last_name: Oñate
- first_name: José H.
full_name: Zagal, José H.
last_name: Zagal
- first_name: Ana
full_name: Pizarro, Ana
last_name: Pizarro
- first_name: J. Francisco
full_name: Silva, J. Francisco
last_name: Silva
- first_name: Carmen
full_name: Castro-Castillo, Carmen
last_name: Castro-Castillo
- first_name: Marcos Caroli
full_name: Rezende, Marcos Caroli
last_name: Rezende
- first_name: Marcos
full_name: Flores, Marcos
last_name: Flores
- first_name: Diego
full_name: Cortés-Arriagada, Diego
last_name: Cortés-Arriagada
- first_name: Alejandro
full_name: Toro-Labbé, Alejandro
last_name: Toro-Labbé
- first_name: Luis M.
full_name: Campos, Luis M.
last_name: Campos
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
- first_name: Ingrid
full_name: Ponce, Ingrid
last_name: Ponce
citation:
ama: 'Gutiérrez-Ceron C, Oñate R, Zagal JH, et al. Molecular conductance versus
inductive effects of axial ligands on the electrocatalytic activity of self-assembled
iron phthalocyanines: The oxygen reduction reaction. Electrochimica Acta.
2019;327. doi:10.1016/j.electacta.2019.134996'
apa: 'Gutiérrez-Ceron, C., Oñate, R., Zagal, J. H., Pizarro, A., Silva, J. F., Castro-Castillo,
C., … Ponce, I. (2019). Molecular conductance versus inductive effects of axial
ligands on the electrocatalytic activity of self-assembled iron phthalocyanines:
The oxygen reduction reaction. Electrochimica Acta. Elsevier. https://doi.org/10.1016/j.electacta.2019.134996'
chicago: 'Gutiérrez-Ceron, Cristian, Rubén Oñate, José H. Zagal, Ana Pizarro, J.
Francisco Silva, Carmen Castro-Castillo, Marcos Caroli Rezende, et al. “Molecular
Conductance versus Inductive Effects of Axial Ligands on the Electrocatalytic
Activity of Self-Assembled Iron Phthalocyanines: The Oxygen Reduction Reaction.”
Electrochimica Acta. Elsevier, 2019. https://doi.org/10.1016/j.electacta.2019.134996.'
ieee: 'C. Gutiérrez-Ceron et al., “Molecular conductance versus inductive
effects of axial ligands on the electrocatalytic activity of self-assembled iron
phthalocyanines: The oxygen reduction reaction,” Electrochimica Acta, vol.
327. Elsevier, 2019.'
ista: 'Gutiérrez-Ceron C, Oñate R, Zagal JH, Pizarro A, Silva JF, Castro-Castillo
C, Rezende MC, Flores M, Cortés-Arriagada D, Toro-Labbé A, Campos LM, Venkataraman
L, Ponce I. 2019. Molecular conductance versus inductive effects of axial ligands
on the electrocatalytic activity of self-assembled iron phthalocyanines: The oxygen
reduction reaction. Electrochimica Acta. 327, 134996.'
mla: 'Gutiérrez-Ceron, Cristian, et al. “Molecular Conductance versus Inductive
Effects of Axial Ligands on the Electrocatalytic Activity of Self-Assembled Iron
Phthalocyanines: The Oxygen Reduction Reaction.” Electrochimica Acta, vol.
327, 134996, Elsevier, 2019, doi:10.1016/j.electacta.2019.134996.'
short: C. Gutiérrez-Ceron, R. Oñate, J.H. Zagal, A. Pizarro, J.F. Silva, C. Castro-Castillo,
M.C. Rezende, M. Flores, D. Cortés-Arriagada, A. Toro-Labbé, L.M. Campos, L. Venkataraman,
I. Ponce, Electrochimica Acta 327 (2019).
date_created: 2024-09-09T07:39:29Z
date_published: 2019-12-10T00:00:00Z
date_updated: 2024-12-10T12:30:09Z
day: '10'
doi: 10.1016/j.electacta.2019.134996
extern: '1'
fulldoi: https://doi.org/10.1016/j.electacta.2019.134996
intvolume: ' 327'
language:
- iso: eng
month: '12'
oa_version: None
publication: Electrochimica Acta
publication_identifier:
issn:
- 0013-4686
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Molecular conductance versus inductive effects of axial ligands on the electrocatalytic
activity of self-assembled iron phthalocyanines: The oxygen reduction reaction'
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 327
year: '2019'
...
---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
_id: '17916'
abstract:
- lang: eng
text: Electric fields have been proposed as having a distinct ability to catalyze
chemical reactions through the stabilization of polar or ionic intermediate transition
states. Although field-assisted catalysis is being researched, the ability to
catalyze reactions in solution using electric fields remains elusive and the understanding
of mechanisms of such catalysis is sparse. Here we show that an electric field
can catalyze the cis-to-trans isomerization of [3]cumulene derivatives in solution,
in a scanning tunneling microscope. We further show that the external electric
field can alter the thermodynamics inhibiting the trans-to-cis reverse reaction,
endowing the selectivity toward trans isomer. Using density functional theory-based
calculations, we find that the applied electric field promotes a zwitterionic
resonance form, which ensures a lower energy transition state for the isomerization
reaction. The field also stabilizes the trans form, relative to the cis, dictating
the cis/trans thermodynamics, driving the equilibrium product exclusively toward
the trans.
article_number: '4482'
article_processing_charge: Yes
article_type: original
author:
- first_name: Yaping
full_name: Zang, Yaping
last_name: Zang
- first_name: Qi
full_name: Zou, Qi
last_name: Zou
- first_name: Tianren
full_name: Fu, Tianren
last_name: Fu
- first_name: Fay
full_name: Ng, Fay
last_name: Ng
- first_name: Brandon
full_name: Fowler, Brandon
last_name: Fowler
- first_name: Jingjing
full_name: Yang, Jingjing
last_name: Yang
- first_name: Hexing
full_name: Li, Hexing
last_name: Li
- first_name: Michael L.
full_name: Steigerwald, Michael L.
last_name: Steigerwald
- first_name: Colin
full_name: Nuckolls, Colin
last_name: Nuckolls
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
citation:
ama: Zang Y, Zou Q, Fu T, et al. Directing isomerization reactions of cumulenes
with electric fields. Nature Communications. 2019;10. doi:10.1038/s41467-019-12487-w
apa: Zang, Y., Zou, Q., Fu, T., Ng, F., Fowler, B., Yang, J., … Venkataraman, L.
(2019). Directing isomerization reactions of cumulenes with electric fields. Nature
Communications. Springer Nature. https://doi.org/10.1038/s41467-019-12487-w
chicago: Zang, Yaping, Qi Zou, Tianren Fu, Fay Ng, Brandon Fowler, Jingjing Yang,
Hexing Li, Michael L. Steigerwald, Colin Nuckolls, and Latha Venkataraman. “Directing
Isomerization Reactions of Cumulenes with Electric Fields.” Nature Communications.
Springer Nature, 2019. https://doi.org/10.1038/s41467-019-12487-w.
ieee: Y. Zang et al., “Directing isomerization reactions of cumulenes with
electric fields,” Nature Communications, vol. 10. Springer Nature, 2019.
ista: Zang Y, Zou Q, Fu T, Ng F, Fowler B, Yang J, Li H, Steigerwald ML, Nuckolls
C, Venkataraman L. 2019. Directing isomerization reactions of cumulenes with electric
fields. Nature Communications. 10, 4482.
mla: Zang, Yaping, et al. “Directing Isomerization Reactions of Cumulenes with Electric
Fields.” Nature Communications, vol. 10, 4482, Springer Nature, 2019, doi:10.1038/s41467-019-12487-w.
short: Y. Zang, Q. Zou, T. Fu, F. Ng, B. Fowler, J. Yang, H. Li, M.L. Steigerwald,
C. Nuckolls, L. Venkataraman, Nature Communications 10 (2019).
date_created: 2024-09-09T07:40:44Z
date_published: 2019-10-02T00:00:00Z
date_updated: 2024-12-10T12:32:33Z
day: '02'
doi: 10.1038/s41467-019-12487-w
extern: '1'
external_id:
pmid:
- '31578333'
fulldoi: https://doi.org/10.1038/s41467-019-12487-w
intvolume: ' 10'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1038/s41467-019-12487-w
month: '10'
oa: 1
oa_version: Published Version
pmid: 1
publication: Nature Communications
publication_identifier:
issn:
- 2041-1723
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Directing isomerization reactions of cumulenes with electric fields
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 10
year: '2019'
...
---
OA_type: closed access
_id: '17917'
abstract:
- lang: eng
text: A single-molecule method has been developed based on the scanning tunneling
microscope (STM) to selectively couple a series of aniline derivatives and create
azobenzenes. The Au-catalyzed oxidative coupling is driven by the local electrochemical
potential at the nanostructured Au STM tip. The products are detected in situ
by measuring the conductance and molecular junction elongation and compared with
analogous measurements of the expected azobenzene derivatives prepared ex situ.
This single-molecule approach is robust, and it can quickly and reproducibly create
reactions for a variety of anilines. We further demonstrate the selective synthesis
of geometric isomers and the assembly of complex molecular architectures by sequential
coupling of complementary anilines, demonstrating unprecedented control over bond
formation at the nanoscale.
article_processing_charge: No
article_type: original
author:
- first_name: Yaping
full_name: Zang, Yaping
last_name: Zang
- first_name: Ilana
full_name: Stone, Ilana
last_name: Stone
- first_name: Michael S.
full_name: Inkpen, Michael S.
last_name: Inkpen
- first_name: Fay
full_name: Ng, Fay
last_name: Ng
- first_name: Tristan H.
full_name: Lambert, Tristan H.
last_name: Lambert
- first_name: Colin
full_name: Nuckolls, Colin
last_name: Nuckolls
- first_name: Michael L.
full_name: Steigerwald, Michael L.
last_name: Steigerwald
- first_name: Xavier
full_name: Roy, Xavier
last_name: Roy
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
citation:
ama: Zang Y, Stone I, Inkpen MS, et al. In situ coupling of single molecules driven
by gold‐catalyzed electrooxidation. Angewandte Chemie International Edition.
2019;58(45):16008-16012. doi:10.1002/anie.201906215
apa: Zang, Y., Stone, I., Inkpen, M. S., Ng, F., Lambert, T. H., Nuckolls, C., …
Venkataraman, L. (2019). In situ coupling of single molecules driven by gold‐catalyzed
electrooxidation. Angewandte Chemie International Edition. Wiley. https://doi.org/10.1002/anie.201906215
chicago: Zang, Yaping, Ilana Stone, Michael S. Inkpen, Fay Ng, Tristan H. Lambert,
Colin Nuckolls, Michael L. Steigerwald, Xavier Roy, and Latha Venkataraman. “In
Situ Coupling of Single Molecules Driven by Gold‐catalyzed Electrooxidation.”
Angewandte Chemie International Edition. Wiley, 2019. https://doi.org/10.1002/anie.201906215.
ieee: Y. Zang et al., “In situ coupling of single molecules driven by gold‐catalyzed
electrooxidation,” Angewandte Chemie International Edition, vol. 58, no.
45. Wiley, pp. 16008–16012, 2019.
ista: Zang Y, Stone I, Inkpen MS, Ng F, Lambert TH, Nuckolls C, Steigerwald ML,
Roy X, Venkataraman L. 2019. In situ coupling of single molecules driven by gold‐catalyzed
electrooxidation. Angewandte Chemie International Edition. 58(45), 16008–16012.
mla: Zang, Yaping, et al. “In Situ Coupling of Single Molecules Driven by Gold‐catalyzed
Electrooxidation.” Angewandte Chemie International Edition, vol. 58, no.
45, Wiley, 2019, pp. 16008–12, doi:10.1002/anie.201906215.
short: Y. Zang, I. Stone, M.S. Inkpen, F. Ng, T.H. Lambert, C. Nuckolls, M.L. Steigerwald,
X. Roy, L. Venkataraman, Angewandte Chemie International Edition 58 (2019) 16008–16012.
date_created: 2024-09-09T07:41:47Z
date_published: 2019-11-04T00:00:00Z
date_updated: 2024-12-10T12:36:30Z
day: '04'
doi: 10.1002/anie.201906215
extern: '1'
external_id:
pmid:
- '31226235'
fulldoi: https://doi.org/10.1002/anie.201906215
intvolume: ' 58'
issue: '45'
language:
- iso: eng
month: '11'
oa_version: None
page: 16008-16012
pmid: 1
publication: Angewandte Chemie International Edition
publication_identifier:
eissn:
- 1521-3773
issn:
- 1433-7851
publication_status: published
publisher: Wiley
quality_controlled: '1'
scopus_import: '1'
status: public
title: In situ coupling of single molecules driven by gold‐catalyzed electrooxidation
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 58
year: '2019'
...
---
OA_type: closed access
_id: '17918'
abstract:
- lang: eng
text: The single-molecule conductance of silanes is suppressed due to destructive
quantum interference in conformations with cisoid dihedral angles along the molecular
backbone. Yet, despite the structural similarity, σ-interference effects have
not been observed in alkanes. Here we report that the methyl substituents used
in silanes are a prerequisite for σ-interference in these systems. Through density
functional theory calculations, we find that the destructive interference is not
evident to the same extent in nonmethylated silanes. We find the same is true
in alkanes as the transmission is significantly suppressed in permethylated cyclic
and bicyclic alkanes. Using scanning tunneling microscope break-junction method
we determine the single-molecule conductance of functionalized cyclohexane and
bicyclo[2.2.2]octane that are found to be higher than that of equivalent permethylated
silanes. Rather than the difference between carbon and silicon atoms in the molecular
backbones, our calculations reveal that it is primarily the difference between
hydrogen and methyl substituents that result in the different electron transport
properties of nonmethylated alkanes and permethylated silanes. Chemical substituents
play an important role in determining the single-molecule conductance of saturated
molecules, and this must be considered when we improve and expand the chemical
design of insulating organic molecules.
article_processing_charge: No
article_type: original
author:
- first_name: Marc H.
full_name: Garner, Marc H.
last_name: Garner
- first_name: Haixing
full_name: Li, Haixing
last_name: Li
- first_name: Madhav
full_name: Neupane, Madhav
last_name: Neupane
- first_name: Qi
full_name: Zou, Qi
last_name: Zou
- first_name: Taifeng
full_name: Liu, Taifeng
last_name: Liu
- first_name: Timothy A.
full_name: Su, Timothy A.
last_name: Su
- first_name: Zhichun
full_name: Shangguan, Zhichun
last_name: Shangguan
- first_name: Daniel W.
full_name: Paley, Daniel W.
last_name: Paley
- first_name: Fay
full_name: Ng, Fay
last_name: Ng
- first_name: Shengxiong
full_name: Xiao, Shengxiong
last_name: Xiao
- first_name: Colin
full_name: Nuckolls, Colin
last_name: Nuckolls
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
- first_name: Gemma C.
full_name: Solomon, Gemma C.
last_name: Solomon
citation:
ama: Garner MH, Li H, Neupane M, et al. Permethylation introduces destructive quantum
interference in saturated silanes. Journal of the American Chemical Society.
2019;141(39):15471-15476. doi:10.1021/jacs.9b06965
apa: Garner, M. H., Li, H., Neupane, M., Zou, Q., Liu, T., Su, T. A., … Solomon,
G. C. (2019). Permethylation introduces destructive quantum interference in saturated
silanes. Journal of the American Chemical Society. American Chemical Society.
https://doi.org/10.1021/jacs.9b06965
chicago: Garner, Marc H., Haixing Li, Madhav Neupane, Qi Zou, Taifeng Liu, Timothy
A. Su, Zhichun Shangguan, et al. “Permethylation Introduces Destructive Quantum
Interference in Saturated Silanes.” Journal of the American Chemical Society.
American Chemical Society, 2019. https://doi.org/10.1021/jacs.9b06965.
ieee: M. H. Garner et al., “Permethylation introduces destructive quantum
interference in saturated silanes,” Journal of the American Chemical Society,
vol. 141, no. 39. American Chemical Society, pp. 15471–15476, 2019.
ista: Garner MH, Li H, Neupane M, Zou Q, Liu T, Su TA, Shangguan Z, Paley DW, Ng
F, Xiao S, Nuckolls C, Venkataraman L, Solomon GC. 2019. Permethylation introduces
destructive quantum interference in saturated silanes. Journal of the American
Chemical Society. 141(39), 15471–15476.
mla: Garner, Marc H., et al. “Permethylation Introduces Destructive Quantum Interference
in Saturated Silanes.” Journal of the American Chemical Society, vol. 141,
no. 39, American Chemical Society, 2019, pp. 15471–76, doi:10.1021/jacs.9b06965.
short: M.H. Garner, H. Li, M. Neupane, Q. Zou, T. Liu, T.A. Su, Z. Shangguan, D.W.
Paley, F. Ng, S. Xiao, C. Nuckolls, L. Venkataraman, G.C. Solomon, Journal of
the American Chemical Society 141 (2019) 15471–15476.
date_created: 2024-09-09T07:42:26Z
date_published: 2019-09-10T00:00:00Z
date_updated: 2024-12-10T12:39:27Z
day: '10'
doi: 10.1021/jacs.9b06965
extern: '1'
external_id:
pmid:
- '31500410'
fulldoi: https://doi.org/10.1021/jacs.9b06965
intvolume: ' 141'
issue: '39'
language:
- iso: eng
month: '09'
oa_version: None
page: 15471-15476
pmid: 1
publication: Journal of the American Chemical Society
publication_identifier:
eissn:
- 1520-5126
issn:
- 0002-7863
publication_status: published
publisher: American Chemical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Permethylation introduces destructive quantum interference in saturated silanes
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 141
year: '2019'
...
---
OA_type: closed access
_id: '17919'
abstract:
- lang: eng
text: The adsorption geometry and the electronic structure of a Blatter radical
derivative on a gold surface were investigated by a combination of high‐resolution
noncontact atomic force microscopy and scanning tunneling microscopy. While the
hybridization with the substrate hinders direct access to the molecular states,
we show that the unpaired‐electron orbital can be probed with Ångström resolution
by mapping the spatial distribution of the Kondo resonance. The Blatter derivative
features a peculiar delocalization of the unpaired‐electron orbital over some
but not all moieties of the molecule, such that the Kondo signature can be related
to the spatial fingerprint of the orbital. We observe a direct correspondence
between these two quantities, including a pronounced nodal plane structure. Finally,
we demonstrate that the spatial signature of the Kondo resonance also persists
upon noncovalent dimerization of molecules.
article_processing_charge: No
article_type: original
author:
- first_name: Laerte L.
full_name: Patera, Laerte L.
last_name: Patera
- first_name: Sophia
full_name: Sokolov, Sophia
last_name: Sokolov
- first_name: Jonathan Z.
full_name: Low, Jonathan Z.
last_name: Low
- first_name: Luis M.
full_name: Campos, Luis M.
last_name: Campos
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
- first_name: Jascha
full_name: Repp, Jascha
last_name: Repp
citation:
ama: Patera LL, Sokolov S, Low JZ, Campos LM, Venkataraman L, Repp J. Resolving
the unpaired‐electron orbital distribution in a stable organic radical by Kondo
resonance mapping. Angewandte Chemie International Edition. 2019;58(32):11063-11067.
doi:10.1002/anie.201904851
apa: Patera, L. L., Sokolov, S., Low, J. Z., Campos, L. M., Venkataraman, L., &
Repp, J. (2019). Resolving the unpaired‐electron orbital distribution in a stable
organic radical by Kondo resonance mapping. Angewandte Chemie International
Edition. Wiley. https://doi.org/10.1002/anie.201904851
chicago: Patera, Laerte L., Sophia Sokolov, Jonathan Z. Low, Luis M. Campos, Latha
Venkataraman, and Jascha Repp. “Resolving the Unpaired‐electron Orbital Distribution
in a Stable Organic Radical by Kondo Resonance Mapping.” Angewandte Chemie
International Edition. Wiley, 2019. https://doi.org/10.1002/anie.201904851.
ieee: L. L. Patera, S. Sokolov, J. Z. Low, L. M. Campos, L. Venkataraman, and J.
Repp, “Resolving the unpaired‐electron orbital distribution in a stable organic
radical by Kondo resonance mapping,” Angewandte Chemie International Edition,
vol. 58, no. 32. Wiley, pp. 11063–11067, 2019.
ista: Patera LL, Sokolov S, Low JZ, Campos LM, Venkataraman L, Repp J. 2019. Resolving
the unpaired‐electron orbital distribution in a stable organic radical by Kondo
resonance mapping. Angewandte Chemie International Edition. 58(32), 11063–11067.
mla: Patera, Laerte L., et al. “Resolving the Unpaired‐electron Orbital Distribution
in a Stable Organic Radical by Kondo Resonance Mapping.” Angewandte Chemie
International Edition, vol. 58, no. 32, Wiley, 2019, pp. 11063–67, doi:10.1002/anie.201904851.
short: L.L. Patera, S. Sokolov, J.Z. Low, L.M. Campos, L. Venkataraman, J. Repp,
Angewandte Chemie International Edition 58 (2019) 11063–11067.
date_created: 2024-09-09T07:43:21Z
date_published: 2019-08-05T00:00:00Z
date_updated: 2024-12-10T12:41:49Z
day: '05'
doi: 10.1002/anie.201904851
extern: '1'
external_id:
pmid:
- '31115954'
fulldoi: https://doi.org/10.1002/anie.201904851
intvolume: ' 58'
issue: '32'
language:
- iso: eng
month: '08'
oa_version: None
page: 11063-11067
pmid: 1
publication: Angewandte Chemie International Edition
publication_identifier:
eissn:
- 1521-3773
issn:
- 1433-7851
publication_status: published
publisher: Wiley
quality_controlled: '1'
scopus_import: '1'
status: public
title: Resolving the unpaired‐electron orbital distribution in a stable organic radical
by Kondo resonance mapping
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 58
year: '2019'
...
---
OA_type: closed access
_id: '17920'
abstract:
- lang: eng
text: Stable organic radicals have potential applications for building organic spintronic
devices. To fulfill this potential, the interface between organic radicals and
metal electrodes must be well characterized. Here, through a combined effort that
includes synthesis, scanning tunneling microscopy, X-ray spectroscopy, and single-molecule
conductance measurements, we comprehensively probe the electronic interaction
between gold metal electrodes and a benchtop stable radical—the Blatter radical.
We find that despite its open-shell character and having a half-filled orbital
close to the Fermi level, the radical is stable on a gold substrate under ultrahigh
vacuum. We observe a Kondo resonance arising from the radical and spectroscopic
signatures of its half-filled orbitals. By contrast, in solution-based single-molecule
conductance measurements, the radical character is lost through oxidation with
charge transfer occurring from the molecule to metal. Our experiments show that
the stability of radical states can be very sensitive to the environment around
the molecule.
article_processing_charge: No
article_type: original
author:
- first_name: Jonathan Z.
full_name: Low, Jonathan Z.
last_name: Low
- first_name: Gregor
full_name: Kladnik, Gregor
last_name: Kladnik
- first_name: Laerte L.
full_name: Patera, Laerte L.
last_name: Patera
- first_name: Sophia
full_name: Sokolov, Sophia
last_name: Sokolov
- first_name: Giacomo
full_name: Lovat, Giacomo
last_name: Lovat
- first_name: Elango
full_name: Kumarasamy, Elango
last_name: Kumarasamy
- first_name: Jascha
full_name: Repp, Jascha
last_name: Repp
- first_name: Luis M.
full_name: Campos, Luis M.
last_name: Campos
- first_name: Dean
full_name: Cvetko, Dean
last_name: Cvetko
- first_name: Alberto
full_name: Morgante, Alberto
last_name: Morgante
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
citation:
ama: Low JZ, Kladnik G, Patera LL, et al. The environment-dependent behavior of
the Blatter radical at the metal–molecule interface. Nano Letters. 2019;19(4):2543-2548.
doi:10.1021/acs.nanolett.9b00275
apa: Low, J. Z., Kladnik, G., Patera, L. L., Sokolov, S., Lovat, G., Kumarasamy,
E., … Venkataraman, L. (2019). The environment-dependent behavior of the Blatter
radical at the metal–molecule interface. Nano Letters. American Chemical
Society. https://doi.org/10.1021/acs.nanolett.9b00275
chicago: Low, Jonathan Z., Gregor Kladnik, Laerte L. Patera, Sophia Sokolov, Giacomo
Lovat, Elango Kumarasamy, Jascha Repp, et al. “The Environment-Dependent Behavior
of the Blatter Radical at the Metal–Molecule Interface.” Nano Letters.
American Chemical Society, 2019. https://doi.org/10.1021/acs.nanolett.9b00275.
ieee: J. Z. Low et al., “The environment-dependent behavior of the Blatter
radical at the metal–molecule interface,” Nano Letters, vol. 19, no. 4.
American Chemical Society, pp. 2543–2548, 2019.
ista: Low JZ, Kladnik G, Patera LL, Sokolov S, Lovat G, Kumarasamy E, Repp J, Campos
LM, Cvetko D, Morgante A, Venkataraman L. 2019. The environment-dependent behavior
of the Blatter radical at the metal–molecule interface. Nano Letters. 19(4), 2543–2548.
mla: Low, Jonathan Z., et al. “The Environment-Dependent Behavior of the Blatter
Radical at the Metal–Molecule Interface.” Nano Letters, vol. 19, no. 4,
American Chemical Society, 2019, pp. 2543–48, doi:10.1021/acs.nanolett.9b00275.
short: J.Z. Low, G. Kladnik, L.L. Patera, S. Sokolov, G. Lovat, E. Kumarasamy, J.
Repp, L.M. Campos, D. Cvetko, A. Morgante, L. Venkataraman, Nano Letters 19 (2019)
2543–2548.
date_created: 2024-09-09T07:44:44Z
date_published: 2019-03-18T00:00:00Z
date_updated: 2024-12-11T07:41:32Z
day: '18'
doi: 10.1021/acs.nanolett.9b00275
extern: '1'
external_id:
pmid:
- '30884240'
fulldoi: https://doi.org/10.1021/acs.nanolett.9b00275
intvolume: ' 19'
issue: '4'
language:
- iso: eng
month: '03'
oa_version: None
page: 2543-2548
pmid: 1
publication: Nano Letters
publication_identifier:
eissn:
- 1530-6992
issn:
- 1530-6984
publication_status: published
publisher: American Chemical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: The environment-dependent behavior of the Blatter radical at the metal–molecule
interface
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 19
year: '2019'
...
---
OA_type: closed access
_id: '17921'
abstract:
- lang: eng
text: The promise of the field of single-molecule electronics is to reveal a new
class of quantum devices that leverages the strong electronic interactions inherent
to subnanometer scale systems. Here, we form Au–molecule–Au junctions using a
custom scanning tunneling microscope and explore charge transport through current–voltage
measurements. We focus on the resonant tunneling regime of two molecules, one
that is primarily an electron conductor and one that conducts primarily holes.
We find that in the high bias regime, junctions that do not rupture demonstrate
reproducible and pronounced negative differential resistance (NDR)-like features
followed by hysteresis with peak-to-valley ratios exceeding 100 in some cases.
Furthermore, we show that both junction rupture and NDR are induced by charging
of the molecular orbital dominating transport and find that the charging is reversible
at lower bias and with time with kinetic time scales on the order of hundreds
of milliseconds. We argue that these results cannot be explained by existing models
of charge transport and likely require theoretical advances describing the transition
from coherent to sequential tunneling. Our work also suggests new rules for operating
single-molecule devices at high bias to obtain highly nonlinear behavior.
article_processing_charge: No
article_type: original
author:
- first_name: E-Dean
full_name: Fung, E-Dean
last_name: Fung
- first_name: David
full_name: Gelbwaser, David
last_name: Gelbwaser
- first_name: Jeffrey
full_name: Taylor, Jeffrey
last_name: Taylor
- first_name: Jonathan
full_name: Low, Jonathan
last_name: Low
- first_name: Jianlong
full_name: Xia, Jianlong
last_name: Xia
- first_name: Iryna
full_name: Davydenko, Iryna
last_name: Davydenko
- first_name: Luis M.
full_name: Campos, Luis M.
last_name: Campos
- first_name: Seth
full_name: Marder, Seth
last_name: Marder
- first_name: Uri
full_name: Peskin, Uri
last_name: Peskin
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
citation:
ama: 'Fung E-D, Gelbwaser D, Taylor J, et al. Breaking down resonance: Nonlinear
transport and the breakdown of coherent tunneling models in single molecule junctions.
Nano Letters. 2019;19(4):2555-2561. doi:10.1021/acs.nanolett.9b00316'
apa: 'Fung, E.-D., Gelbwaser, D., Taylor, J., Low, J., Xia, J., Davydenko, I., …
Venkataraman, L. (2019). Breaking down resonance: Nonlinear transport and the
breakdown of coherent tunneling models in single molecule junctions. Nano Letters.
American Chemical Society. https://doi.org/10.1021/acs.nanolett.9b00316'
chicago: 'Fung, E-Dean, David Gelbwaser, Jeffrey Taylor, Jonathan Low, Jianlong
Xia, Iryna Davydenko, Luis M. Campos, Seth Marder, Uri Peskin, and Latha Venkataraman.
“Breaking down Resonance: Nonlinear Transport and the Breakdown of Coherent Tunneling
Models in Single Molecule Junctions.” Nano Letters. American Chemical Society,
2019. https://doi.org/10.1021/acs.nanolett.9b00316.'
ieee: 'E.-D. Fung et al., “Breaking down resonance: Nonlinear transport and
the breakdown of coherent tunneling models in single molecule junctions,” Nano
Letters, vol. 19, no. 4. American Chemical Society, pp. 2555–2561, 2019.'
ista: 'Fung E-D, Gelbwaser D, Taylor J, Low J, Xia J, Davydenko I, Campos LM, Marder
S, Peskin U, Venkataraman L. 2019. Breaking down resonance: Nonlinear transport
and the breakdown of coherent tunneling models in single molecule junctions. Nano
Letters. 19(4), 2555–2561.'
mla: 'Fung, E. Dean, et al. “Breaking down Resonance: Nonlinear Transport and the
Breakdown of Coherent Tunneling Models in Single Molecule Junctions.” Nano
Letters, vol. 19, no. 4, American Chemical Society, 2019, pp. 2555–61, doi:10.1021/acs.nanolett.9b00316.'
short: E.-D. Fung, D. Gelbwaser, J. Taylor, J. Low, J. Xia, I. Davydenko, L.M. Campos,
S. Marder, U. Peskin, L. Venkataraman, Nano Letters 19 (2019) 2555–2561.
date_created: 2024-09-09T07:46:01Z
date_published: 2019-03-01T00:00:00Z
date_updated: 2024-12-11T07:48:13Z
day: '01'
doi: 10.1021/acs.nanolett.9b00316
extern: '1'
external_id:
pmid:
- '30821465'
fulldoi: https://doi.org/10.1021/acs.nanolett.9b00316
intvolume: ' 19'
issue: '4'
language:
- iso: eng
month: '03'
oa_version: None
page: 2555-2561
pmid: 1
publication: Nano Letters
publication_identifier:
eissn:
- 1530-6992
issn:
- 1530-6984
publication_status: published
publisher: American Chemical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Breaking down resonance: Nonlinear transport and the breakdown of coherent
tunneling models in single molecule junctions'
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 19
year: '2019'
...
---
OA_type: closed access
_id: '17922'
abstract:
- lang: eng
text: Gold–thiol contacts are ubiquitous across the physical and biological sciences
in connecting organic molecules to surfaces. When thiols bind to gold in self-assembled
monolayers (SAMs) the fate of the hydrogen remains a subject of profound debate—with
implications for our understanding of their physical properties, spectroscopic
features and formation mechanism(s). Exploiting measurements of the transmission
through a molecular junction, which is highly sensitive to the nature of the molecule–electrode
contact, we demonstrate here that the nature of the gold–sulfur bond in SAMs can
be probed via single-molecule conductance measurements. Critically, we find that
SAM measurements of dithiol-terminated molecular junctions yield a significantly
lower conductance than solution measurements of the same molecule. Through numerous
control experiments, conductance noise analysis and transport calculations based
on density functional theory, we show that the gold–sulfur bond in SAMs prepared
from the solution deposition of dithiols does not have chemisorbed character,
which strongly suggests that under these widely used preparation conditions the
hydrogen is retained.
article_processing_charge: No
article_type: original
author:
- first_name: Michael S.
full_name: Inkpen, Michael S.
last_name: Inkpen
- first_name: Zhen–Fei
full_name: Liu, Zhen–Fei
last_name: Liu
- first_name: Haixing
full_name: Li, Haixing
last_name: Li
- first_name: Luis M.
full_name: Campos, Luis M.
last_name: Campos
- first_name: Jeffrey B.
full_name: Neaton, Jeffrey B.
last_name: Neaton
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
citation:
ama: Inkpen MS, Liu Z, Li H, Campos LM, Neaton JB, Venkataraman L. Non-chemisorbed
gold–sulfur binding prevails in self-assembled monolayers. Nature Chemistry.
2019;11(4):351-358. doi:10.1038/s41557-019-0216-y
apa: Inkpen, M. S., Liu, Z., Li, H., Campos, L. M., Neaton, J. B., & Venkataraman,
L. (2019). Non-chemisorbed gold–sulfur binding prevails in self-assembled monolayers.
Nature Chemistry. Springer Nature. https://doi.org/10.1038/s41557-019-0216-y
chicago: Inkpen, Michael S., Zhen–Fei Liu, Haixing Li, Luis M. Campos, Jeffrey B.
Neaton, and Latha Venkataraman. “Non-Chemisorbed Gold–Sulfur Binding Prevails
in Self-Assembled Monolayers.” Nature Chemistry. Springer Nature, 2019.
https://doi.org/10.1038/s41557-019-0216-y.
ieee: M. S. Inkpen, Z. Liu, H. Li, L. M. Campos, J. B. Neaton, and L. Venkataraman,
“Non-chemisorbed gold–sulfur binding prevails in self-assembled monolayers,” Nature
Chemistry, vol. 11, no. 4. Springer Nature, pp. 351–358, 2019.
ista: Inkpen MS, Liu Z, Li H, Campos LM, Neaton JB, Venkataraman L. 2019. Non-chemisorbed
gold–sulfur binding prevails in self-assembled monolayers. Nature Chemistry. 11(4),
351–358.
mla: Inkpen, Michael S., et al. “Non-Chemisorbed Gold–Sulfur Binding Prevails in
Self-Assembled Monolayers.” Nature Chemistry, vol. 11, no. 4, Springer
Nature, 2019, pp. 351–58, doi:10.1038/s41557-019-0216-y.
short: M.S. Inkpen, Z. Liu, H. Li, L.M. Campos, J.B. Neaton, L. Venkataraman, Nature
Chemistry 11 (2019) 351–358.
date_created: 2024-09-09T07:48:03Z
date_published: 2019-04-01T00:00:00Z
date_updated: 2024-12-11T08:00:35Z
day: '01'
doi: 10.1038/s41557-019-0216-y
extern: '1'
external_id:
pmid:
- '30833721'
fulldoi: https://doi.org/10.1038/s41557-019-0216-y
intvolume: ' 11'
issue: '4'
language:
- iso: eng
month: '04'
oa_version: None
page: 351-358
pmid: 1
publication: Nature Chemistry
publication_identifier:
eissn:
- 1755-4349
issn:
- 1755-4330
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Non-chemisorbed gold–sulfur binding prevails in self-assembled monolayers
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 11
year: '2019'
...
---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
_id: '17924'
abstract:
- lang: eng
text: We demonstrate that imidazole based π–π stacked dimers form strong and efficient
conductance pathways in single-molecule junctions using the scanning-tunneling
microscope-break junction (STM-BJ) technique and density functional theory-based
calculations. We first characterize an imidazole-gold contact by measuring the
conductance of imidazolyl-terminated alkanes (im-N-im, N = 3–6). We show that
the conductance of these alkanes decays exponentially with increasing length,
indicating that the mechanism for electron transport is through tunneling or super-exchange.
We also reveal that π–π stacked dimers can be formed between imidazoles and have
better coupling than through-bond tunneling. These experimental results are rationalized
by calculations of molecular junction transmission using non-equilibrium Green's
function formalism. This study verifies the capability of imidazole as a Au-binding
ligand to form stable single- and π-stacked molecule junctions at room temperature.
article_processing_charge: Yes
article_type: original
author:
- first_name: Tianren
full_name: Fu, Tianren
last_name: Fu
- first_name: Shanelle
full_name: Smith, Shanelle
last_name: Smith
- first_name: María
full_name: Camarasa-Gómez, María
last_name: Camarasa-Gómez
- first_name: Xiaofang
full_name: Yu, Xiaofang
last_name: Yu
- first_name: Jiayi
full_name: Xue, Jiayi
last_name: Xue
- first_name: Colin
full_name: Nuckolls, Colin
last_name: Nuckolls
- first_name: Ferdinand
full_name: Evers, Ferdinand
last_name: Evers
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
- first_name: Sujun
full_name: Wei, Sujun
last_name: Wei
citation:
ama: Fu T, Smith S, Camarasa-Gómez M, et al. Enhanced coupling through π-stacking
in imidazole-based molecular junctions. Chemical Science. 2019;10(43):9998-10002.
doi:10.1039/c9sc03760h
apa: Fu, T., Smith, S., Camarasa-Gómez, M., Yu, X., Xue, J., Nuckolls, C., … Wei,
S. (2019). Enhanced coupling through π-stacking in imidazole-based molecular junctions.
Chemical Science. Royal Society of Chemistry. https://doi.org/10.1039/c9sc03760h
chicago: Fu, Tianren, Shanelle Smith, María Camarasa-Gómez, Xiaofang Yu, Jiayi Xue,
Colin Nuckolls, Ferdinand Evers, Latha Venkataraman, and Sujun Wei. “Enhanced
Coupling through π-Stacking in Imidazole-Based Molecular Junctions.” Chemical
Science. Royal Society of Chemistry, 2019. https://doi.org/10.1039/c9sc03760h.
ieee: T. Fu et al., “Enhanced coupling through π-stacking in imidazole-based
molecular junctions,” Chemical Science, vol. 10, no. 43. Royal Society
of Chemistry, pp. 9998–10002, 2019.
ista: Fu T, Smith S, Camarasa-Gómez M, Yu X, Xue J, Nuckolls C, Evers F, Venkataraman
L, Wei S. 2019. Enhanced coupling through π-stacking in imidazole-based molecular
junctions. Chemical Science. 10(43), 9998–10002.
mla: Fu, Tianren, et al. “Enhanced Coupling through π-Stacking in Imidazole-Based
Molecular Junctions.” Chemical Science, vol. 10, no. 43, Royal Society
of Chemistry, 2019, pp. 9998–10002, doi:10.1039/c9sc03760h.
short: T. Fu, S. Smith, M. Camarasa-Gómez, X. Yu, J. Xue, C. Nuckolls, F. Evers,
L. Venkataraman, S. Wei, Chemical Science 10 (2019) 9998–10002.
date_created: 2024-09-09T07:49:24Z
date_published: 2019-09-16T00:00:00Z
date_updated: 2024-12-11T08:08:34Z
day: '16'
doi: 10.1039/c9sc03760h
extern: '1'
external_id:
pmid:
- '32055356'
fulldoi: https://doi.org/10.1039/c9sc03760h
intvolume: ' 10'
issue: '43'
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc/3.0/
main_file_link:
- open_access: '1'
url: https://doi.org/10.1039/C9SC03760H
month: '09'
oa: 1
oa_version: Published Version
page: 9998-10002
pmid: 1
publication: Chemical Science
publication_identifier:
eissn:
- 2041-6539
issn:
- 2041-6520
publication_status: published
publisher: Royal Society of Chemistry
quality_controlled: '1'
scopus_import: '1'
status: public
title: Enhanced coupling through π-stacking in imidazole-based molecular junctions
tmp:
image: /images/cc_by_nc.png
legal_code_url: https://creativecommons.org/licenses/by-nc/3.0/legalcode
name: Creative Commons Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0)
short: CC BY-NC (3.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 10
year: '2019'
...
---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
_id: '17925'
abstract:
- lang: eng
text: Recent years have seen tremendous progress towards understanding the relation
between the molecular structure and function of organic field effect transistors.
The metrics for organic field effect transistors, which are characterized by mobility
and the on/off ratio, are known to be enhanced when the intermolecular interaction
is strong and the intramolecular reorganization energy is low. While these requirements
are adequate when describing organic field effect transistors with simple and
planar aromatic molecular components, they are insufficient for complex building
blocks, which have the potential to localize a carrier on the molecule. Here,
we show that intramolecular conductivity can play a role in controlling device
characteristics of organic field effect transistors made with macrocycle building
blocks. We use two isomeric macrocyclic semiconductors that consist of perylene
diimides linked with bithiophenes and find that the trans-linked macrocycle has
a higher mobility than the cis-based device. Through a combination of single molecule
junction conductance measurements of the components of the macrocycles, control
experiments with acyclic counterparts to the macrocycles, and analyses of each
of the materials using spectroscopy, electrochemistry, and density functional
theory, we attribute the difference in electron mobility of the OFETs created
with the two isomers to the difference in intramolecular conductivity of the two
macrocycles.
article_processing_charge: Yes
article_type: original
author:
- first_name: Melissa L.
full_name: Ball, Melissa L.
last_name: Ball
- first_name: Boyuan
full_name: Zhang, Boyuan
last_name: Zhang
- first_name: Tianren
full_name: Fu, Tianren
last_name: Fu
- first_name: Ayden M.
full_name: Schattman, Ayden M.
last_name: Schattman
- first_name: Daniel W.
full_name: Paley, Daniel W.
last_name: Paley
- first_name: Fay
full_name: Ng, Fay
last_name: Ng
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
- first_name: Colin
full_name: Nuckolls, Colin
last_name: Nuckolls
- first_name: Michael L.
full_name: Steigerwald, Michael L.
last_name: Steigerwald
citation:
ama: Ball ML, Zhang B, Fu T, et al. The importance of intramolecular conductivity
in three dimensional molecular solids. Chemical Science. 2019;10(40):9339-9344.
doi:10.1039/c9sc03144h
apa: Ball, M. L., Zhang, B., Fu, T., Schattman, A. M., Paley, D. W., Ng, F., … Steigerwald,
M. L. (2019). The importance of intramolecular conductivity in three dimensional
molecular solids. Chemical Science. Royal Society of Chemistry. https://doi.org/10.1039/c9sc03144h
chicago: Ball, Melissa L., Boyuan Zhang, Tianren Fu, Ayden M. Schattman, Daniel
W. Paley, Fay Ng, Latha Venkataraman, Colin Nuckolls, and Michael L. Steigerwald.
“The Importance of Intramolecular Conductivity in Three Dimensional Molecular
Solids.” Chemical Science. Royal Society of Chemistry, 2019. https://doi.org/10.1039/c9sc03144h.
ieee: M. L. Ball et al., “The importance of intramolecular conductivity in
three dimensional molecular solids,” Chemical Science, vol. 10, no. 40.
Royal Society of Chemistry, pp. 9339–9344, 2019.
ista: Ball ML, Zhang B, Fu T, Schattman AM, Paley DW, Ng F, Venkataraman L, Nuckolls
C, Steigerwald ML. 2019. The importance of intramolecular conductivity in three
dimensional molecular solids. Chemical Science. 10(40), 9339–9344.
mla: Ball, Melissa L., et al. “The Importance of Intramolecular Conductivity in
Three Dimensional Molecular Solids.” Chemical Science, vol. 10, no. 40,
Royal Society of Chemistry, 2019, pp. 9339–44, doi:10.1039/c9sc03144h.
short: M.L. Ball, B. Zhang, T. Fu, A.M. Schattman, D.W. Paley, F. Ng, L. Venkataraman,
C. Nuckolls, M.L. Steigerwald, Chemical Science 10 (2019) 9339–9344.
date_created: 2024-09-09T07:51:38Z
date_published: 2019-08-28T00:00:00Z
date_updated: 2024-12-11T08:12:09Z
day: '28'
doi: 10.1039/c9sc03144h
extern: '1'
external_id:
pmid:
- '32110297'
fulldoi: https://doi.org/10.1039/c9sc03144h
intvolume: ' 10'
issue: '40'
language:
- iso: eng
month: '08'
oa_version: Published Version
page: 9339-9344
pmid: 1
publication: Chemical Science
publication_identifier:
eissn:
- 2041-6539
issn:
- 2041-6520
publication_status: published
publisher: Royal Society of Chemistry
quality_controlled: '1'
scopus_import: '1'
status: public
title: The importance of intramolecular conductivity in three dimensional molecular
solids
tmp:
image: /images/cc_by_nc.png
legal_code_url: https://creativecommons.org/licenses/by-nc/3.0/legalcode
name: Creative Commons Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0)
short: CC BY-NC (3.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 10
year: '2019'
...
---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
_id: '17926'
abstract:
- lang: eng
text: N-heterocyclic carbenes (NHCs) bind very strongly to transition metals due
to their unique electronic structure featuring a divalent carbon atom with a lone
pair in a highly directional sp2-hybridized orbital. As such, they can be assembled
into monolayers on metal surfaces that have enhanced stability compared to their
thiol-based counterparts. The utility of NHCs to form such robust self-assembled
monolayers (SAMs) was only recently recognized and many fundamental questions
remain. Here we investigate the structure and geometry of a series of NHCs on
Au(111) using high-resolution X-ray photoelectron spectroscopy and density functional
theory calculations. We find that the N-substituents on the NHC ring strongly
affect the molecule–metal interaction and steer the orientation of molecules in
the surface layer. In contrast to previous reports, our experimental and theoretical
results provide unequivocal evidence that NHCs with N-methyl substituents bind
to undercoordinated adatoms to form flat-lying complexes. In these SAMs, the donor–acceptor
interaction between the NHC lone pair and the undercoordinated Au adatom is primarily
responsible for the strong bonding of the molecules to the surface. NHCs with
bulkier N-substituents prevent the formation of such complexes by forcing the
molecules into an upright orientation. Our work provides unique insights into
the bonding and geometry of NHC monolayers; more generally, it charts a clear
path to manipulating the interaction between NHCs and metal surfaces using traditional
coordination chemistry synthetic strategies.
article_processing_charge: Yes
article_type: original
author:
- first_name: Giacomo
full_name: Lovat, Giacomo
last_name: Lovat
- first_name: Evan A.
full_name: Doud, Evan A.
last_name: Doud
- first_name: Deyu
full_name: Lu, Deyu
last_name: Lu
- first_name: Gregor
full_name: Kladnik, Gregor
last_name: Kladnik
- first_name: Michael S.
full_name: Inkpen, Michael S.
last_name: Inkpen
- first_name: Michael L.
full_name: Steigerwald, Michael L.
last_name: Steigerwald
- first_name: Dean
full_name: Cvetko, Dean
last_name: Cvetko
- first_name: Mark S.
full_name: Hybertsen, Mark S.
last_name: Hybertsen
- first_name: Alberto
full_name: Morgante, Alberto
last_name: Morgante
- first_name: Xavier
full_name: Roy, Xavier
last_name: Roy
- first_name: Latha
full_name: Venkataraman, Latha
id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf
last_name: Venkataraman
orcid: 0000-0002-6957-6089
citation:
ama: Lovat G, Doud EA, Lu D, et al. Determination of the structure and geometry
of N-heterocyclic carbenes on Au(111) using high-resolution spectroscopy. Chemical
Science. 2019;10(3):930-935. doi:10.1039/c8sc03502d
apa: Lovat, G., Doud, E. A., Lu, D., Kladnik, G., Inkpen, M. S., Steigerwald, M.
L., … Venkataraman, L. (2019). Determination of the structure and geometry of
N-heterocyclic carbenes on Au(111) using high-resolution spectroscopy. Chemical
Science. Royal Society of Chemistry. https://doi.org/10.1039/c8sc03502d
chicago: Lovat, Giacomo, Evan A. Doud, Deyu Lu, Gregor Kladnik, Michael S. Inkpen,
Michael L. Steigerwald, Dean Cvetko, et al. “Determination of the Structure and
Geometry of N-Heterocyclic Carbenes on Au(111) Using High-Resolution Spectroscopy.”
Chemical Science. Royal Society of Chemistry, 2019. https://doi.org/10.1039/c8sc03502d.
ieee: G. Lovat et al., “Determination of the structure and geometry of N-heterocyclic
carbenes on Au(111) using high-resolution spectroscopy,” Chemical Science,
vol. 10, no. 3. Royal Society of Chemistry, pp. 930–935, 2019.
ista: Lovat G, Doud EA, Lu D, Kladnik G, Inkpen MS, Steigerwald ML, Cvetko D, Hybertsen
MS, Morgante A, Roy X, Venkataraman L. 2019. Determination of the structure and
geometry of N-heterocyclic carbenes on Au(111) using high-resolution spectroscopy.
Chemical Science. 10(3), 930–935.
mla: Lovat, Giacomo, et al. “Determination of the Structure and Geometry of N-Heterocyclic
Carbenes on Au(111) Using High-Resolution Spectroscopy.” Chemical Science,
vol. 10, no. 3, Royal Society of Chemistry, 2019, pp. 930–35, doi:10.1039/c8sc03502d.
short: G. Lovat, E.A. Doud, D. Lu, G. Kladnik, M.S. Inkpen, M.L. Steigerwald, D.
Cvetko, M.S. Hybertsen, A. Morgante, X. Roy, L. Venkataraman, Chemical Science
10 (2019) 930–935.
date_created: 2024-09-09T07:52:37Z
date_published: 2019-03-01T00:00:00Z
date_updated: 2024-12-11T08:18:23Z
day: '01'
doi: 10.1039/c8sc03502d
extern: '1'
external_id:
pmid:
- '30774887'
fulldoi: https://doi.org/10.1039/c8sc03502d
intvolume: ' 10'
issue: '3'
language:
- iso: eng
month: '03'
oa_version: Published Version
page: 930-935
pmid: 1
publication: Chemical Science
publication_identifier:
eissn:
- 2041-6539
issn:
- 2041-6520
publication_status: published
publisher: Royal Society of Chemistry
quality_controlled: '1'
scopus_import: '1'
status: public
title: Determination of the structure and geometry of N-heterocyclic carbenes on Au(111)
using high-resolution spectroscopy
tmp:
image: /images/cc_by_nc.png
legal_code_url: https://creativecommons.org/licenses/by-nc/3.0/legalcode
name: Creative Commons Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0)
short: CC BY-NC (3.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 10
year: '2019'
...
---
_id: '18195'
abstract:
- lang: eng
text: Phase transitions are driven by collective fluctuations of a system’s constituents
that emerge at a critical point1. This mechanism has been extensively explored
for classical and quantum systems in equilibrium, whose critical behaviour is
described by the general theory of phase transitions. Recently, however, fundamentally
distinct phase transitions have been discovered for out-of-equilibrium quantum
systems, which can exhibit critical behaviour that defies this description and
is not well understood1. A paradigmatic example is the many-body localization
(MBL) transition, which marks the breakdown of thermalization in an isolated quantum
many-body system as its disorder increases beyond a critical value2,3,4,5,6,7,8,9,10,11.
Characterizing quantum critical behaviour in an MBL system requires probing its
entanglement over space and time4,5,7, which has proved experimentally challenging
owing to stringent requirements on quantum state preparation and system isolation.
Here we observe quantum critical behaviour at the MBL transition in a disordered
Bose–Hubbard system and characterize its entanglement via its multi-point quantum
correlations. We observe the emergence of strong correlations, accompanied by
the onset of anomalous diffusive transport throughout the system, and verify their
critical nature by measuring their dependence on the system size. The correlations
extend to high orders in the quantum critical regime and appear to form via a
sparse network of many-body resonances that spans the entire system12,13. Our
results connect the macroscopic phenomenology of the transition to the system’s
microscopic structure of quantum correlations, and they provide an essential step
towards understanding criticality and universality in non-equilibrium systems1,7,13.
article_processing_charge: No
article_type: letter_note
arxiv: 1
author:
- first_name: Matthew
full_name: Rispoli, Matthew
last_name: Rispoli
- first_name: Alexander
full_name: Lukin, Alexander
last_name: Lukin
- first_name: Robert
full_name: Schittko, Robert
last_name: Schittko
- first_name: Sooshin
full_name: Kim, Sooshin
last_name: Kim
- first_name: M. Eric
full_name: Tai, M. Eric
last_name: Tai
- first_name: Julian
full_name: Leonard, Julian
id: b75b3f45-7995-11ef-9bfd-9a9cd02c3577
last_name: Leonard
- first_name: Markus
full_name: Greiner, Markus
last_name: Greiner
citation:
ama: Rispoli M, Lukin A, Schittko R, et al. Quantum critical behaviour at the many-body
localization transition. Nature. 2019;573(7774):385-389. doi:10.1038/s41586-019-1527-2
apa: Rispoli, M., Lukin, A., Schittko, R., Kim, S., Tai, M. E., Leonard, J., &
Greiner, M. (2019). Quantum critical behaviour at the many-body localization transition.
Nature. Springer Nature. https://doi.org/10.1038/s41586-019-1527-2
chicago: Rispoli, Matthew, Alexander Lukin, Robert Schittko, Sooshin Kim, M. Eric
Tai, Julian Leonard, and Markus Greiner. “Quantum Critical Behaviour at the Many-Body
Localization Transition.” Nature. Springer Nature, 2019. https://doi.org/10.1038/s41586-019-1527-2.
ieee: M. Rispoli et al., “Quantum critical behaviour at the many-body localization
transition,” Nature, vol. 573, no. 7774. Springer Nature, pp. 385–389,
2019.
ista: Rispoli M, Lukin A, Schittko R, Kim S, Tai ME, Leonard J, Greiner M. 2019.
Quantum critical behaviour at the many-body localization transition. Nature. 573(7774),
385–389.
mla: Rispoli, Matthew, et al. “Quantum Critical Behaviour at the Many-Body Localization
Transition.” Nature, vol. 573, no. 7774, Springer Nature, 2019, pp. 385–89,
doi:10.1038/s41586-019-1527-2.
short: M. Rispoli, A. Lukin, R. Schittko, S. Kim, M.E. Tai, J. Leonard, M. Greiner,
Nature 573 (2019) 385–389.
date_created: 2024-10-07T11:48:26Z
date_published: 2019-09-04T00:00:00Z
date_updated: 2024-10-08T09:33:30Z
day: '04'
doi: 10.1038/s41586-019-1527-2
extern: '1'
external_id:
arxiv:
- '1812.06959'
pmid:
- '31485075'
fulldoi: https://doi.org/10.1038/s41586-019-1527-2
intvolume: ' 573'
issue: '7774'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.48550/arXiv.1812.06959
month: '09'
oa: 1
oa_version: Preprint
page: 385-389
pmid: 1
publication: Nature
publication_identifier:
eissn:
- 1476-4687
issn:
- 0028-0836
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Quantum critical behaviour at the many-body localization transition
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 573
year: '2019'
...
---
_id: '18196'
abstract:
- lang: eng
text: An interacting quantum system that is subject to disorder may cease to thermalize
owing to localization of its constituents, thereby marking the breakdown of thermodynamics.
The key to understanding this phenomenon lies in the system’s entanglement, which
is experimentally challenging to measure. We realize such a many-body–localized
system in a disordered Bose-Hubbard chain and characterize its entanglement properties
through particle fluctuations and correlations. We observe that the particles
become localized, suppressing transport and preventing the thermalization of subsystems.
Notably, we measure the development of nonlocal correlations, whose evolution
is consistent with a logarithmic growth of entanglement entropy, the hallmark
of many-body localization. Our work experimentally establishes many-body localization
as a qualitatively distinct phenomenon from localization in noninteracting, disordered
systems.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Alexander
full_name: Lukin, Alexander
last_name: Lukin
- first_name: Matthew
full_name: Rispoli, Matthew
last_name: Rispoli
- first_name: Robert
full_name: Schittko, Robert
last_name: Schittko
- first_name: M. Eric
full_name: Tai, M. Eric
last_name: Tai
- first_name: Adam M.
full_name: Kaufman, Adam M.
last_name: Kaufman
- first_name: Soonwon
full_name: Choi, Soonwon
last_name: Choi
- first_name: Vedika
full_name: Khemani, Vedika
last_name: Khemani
- first_name: Julian
full_name: Leonard, Julian
id: b75b3f45-7995-11ef-9bfd-9a9cd02c3577
last_name: Leonard
- first_name: Markus
full_name: Greiner, Markus
last_name: Greiner
citation:
ama: Lukin A, Rispoli M, Schittko R, et al. Probing entanglement in a many-body–localized
system. Science. 2019;364(6437):256-260. doi:10.1126/science.aau0818
apa: Lukin, A., Rispoli, M., Schittko, R., Tai, M. E., Kaufman, A. M., Choi, S.,
… Greiner, M. (2019). Probing entanglement in a many-body–localized system. Science.
American Association for the Advancement of Science. https://doi.org/10.1126/science.aau0818
chicago: Lukin, Alexander, Matthew Rispoli, Robert Schittko, M. Eric Tai, Adam M.
Kaufman, Soonwon Choi, Vedika Khemani, Julian Leonard, and Markus Greiner. “Probing
Entanglement in a Many-Body–Localized System.” Science. American Association
for the Advancement of Science, 2019. https://doi.org/10.1126/science.aau0818.
ieee: A. Lukin et al., “Probing entanglement in a many-body–localized system,”
Science, vol. 364, no. 6437. American Association for the Advancement of
Science, pp. 256–260, 2019.
ista: Lukin A, Rispoli M, Schittko R, Tai ME, Kaufman AM, Choi S, Khemani V, Leonard
J, Greiner M. 2019. Probing entanglement in a many-body–localized system. Science.
364(6437), 256–260.
mla: Lukin, Alexander, et al. “Probing Entanglement in a Many-Body–Localized System.”
Science, vol. 364, no. 6437, American Association for the Advancement of
Science, 2019, pp. 256–60, doi:10.1126/science.aau0818.
short: A. Lukin, M. Rispoli, R. Schittko, M.E. Tai, A.M. Kaufman, S. Choi, V. Khemani,
J. Leonard, M. Greiner, Science 364 (2019) 256–260.
date_created: 2024-10-07T11:48:43Z
date_published: 2019-04-19T00:00:00Z
date_updated: 2024-10-08T09:28:42Z
day: '19'
doi: 10.1126/science.aau0818
extern: '1'
external_id:
arxiv:
- '1805.09819'
fulldoi: https://doi.org/10.1126/science.aau0818
intvolume: ' 364'
issue: '6437'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.48550/arXiv.1805.09819
month: '04'
oa: 1
oa_version: Preprint
page: 256-260
publication: Science
publication_identifier:
eissn:
- 1095-9203
issn:
- 0036-8075
publication_status: published
publisher: American Association for the Advancement of Science
quality_controlled: '1'
scopus_import: '1'
status: public
title: Probing entanglement in a many-body–localized system
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 364
year: '2019'
...
---
_id: '18256'
abstract:
- lang: eng
text: '"Beauty is in the eye of the beholder." This maxim, emphasizing the subjectivity
of the perception of beauty, has enjoyed a wide consensus since ancient times.
In the digital era, data-driven methods have been shown to be able to predict
human-assigned beauty scores for facial images. In this work, we augment this
ability and train a generative model that generates faces conditioned on a requested
beauty score. In addition, we show how this trained generator can be used to "beautify"
an input face image. By doing so, we achieve an unsupervised beautification model,
in the sense that it relies on no ground truth target images. Our implementation
is available on: https://github.com/beholdergan/Beholder-GAN.'
article_number: '8803807'
article_processing_charge: No
arxiv: 1
author:
- first_name: Nir
full_name: Diamant, Nir
last_name: Diamant
- first_name: Dean
full_name: Zadok, Dean
last_name: Zadok
- first_name: Chaim
full_name: Baskin, Chaim
last_name: Baskin
- first_name: Eli
full_name: Schwartz, Eli
last_name: Schwartz
- first_name: Alexander
full_name: Bronstein, Alexander
id: 58f3726e-7cba-11ef-ad8b-e6e8cb3904e6
last_name: Bronstein
orcid: 0000-0001-9699-8730
citation:
ama: 'Diamant N, Zadok D, Baskin C, Schwartz E, Bronstein AM. Beholder-Gan: Generation
and beautification of facial images with conditioning on their beauty level. In:
2019 IEEE International Conference on Image Processing (ICIP). IEEE; 2019.
doi:10.1109/icip.2019.8803807'
apa: 'Diamant, N., Zadok, D., Baskin, C., Schwartz, E., & Bronstein, A. M. (2019).
Beholder-Gan: Generation and beautification of facial images with conditioning
on their beauty level. In 2019 IEEE International Conference on Image Processing
(ICIP). Taipei, Taiwan: IEEE. https://doi.org/10.1109/icip.2019.8803807'
chicago: 'Diamant, Nir, Dean Zadok, Chaim Baskin, Eli Schwartz, and Alex M. Bronstein.
“Beholder-Gan: Generation and Beautification of Facial Images with Conditioning
on Their Beauty Level.” In 2019 IEEE International Conference on Image Processing
(ICIP). IEEE, 2019. https://doi.org/10.1109/icip.2019.8803807.'
ieee: 'N. Diamant, D. Zadok, C. Baskin, E. Schwartz, and A. M. Bronstein, “Beholder-Gan:
Generation and beautification of facial images with conditioning on their beauty
level,” in 2019 IEEE International Conference on Image Processing (ICIP),
Taipei, Taiwan, 2019.'
ista: 'Diamant N, Zadok D, Baskin C, Schwartz E, Bronstein AM. 2019. Beholder-Gan:
Generation and beautification of facial images with conditioning on their beauty
level. 2019 IEEE International Conference on Image Processing (ICIP). 26th IEEE
International Conference on Image Processing, 8803807.'
mla: 'Diamant, Nir, et al. “Beholder-Gan: Generation and Beautification of Facial
Images with Conditioning on Their Beauty Level.” 2019 IEEE International Conference
on Image Processing (ICIP), 8803807, IEEE, 2019, doi:10.1109/icip.2019.8803807.'
short: N. Diamant, D. Zadok, C. Baskin, E. Schwartz, A.M. Bronstein, in:, 2019 IEEE
International Conference on Image Processing (ICIP), IEEE, 2019.
conference:
end_date: 2019-09-25
location: Taipei, Taiwan
name: 26th IEEE International Conference on Image Processing
start_date: 2019-09-22
date_created: 2024-10-08T13:07:32Z
date_published: 2019-08-26T00:00:00Z
date_updated: 2024-12-05T15:59:29Z
day: '26'
doi: 10.1109/icip.2019.8803807
extern: '1'
external_id:
arxiv:
- '1902.02593'
fulldoi: https://doi.org/10.1109/icip.2019.8803807
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.48550/arXiv.1902.02593
month: '08'
oa: 1
oa_version: Preprint
publication: 2019 IEEE International Conference on Image Processing (ICIP)
publication_identifier:
eissn:
- 2381-8549
isbn:
- '9781538662502'
publication_status: published
publisher: IEEE
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Beholder-Gan: Generation and beautification of facial images with conditioning
on their beauty level'
type: conference
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
year: '2019'
...
---
_id: '18257'
abstract:
- lang: eng
text: We consider the problem of localizing relevant subsets of non-rigid geometric
shapes given only a partial 3D query as the input. Such problems arise in several
challenging tasks in 3D vision and graphics, including partial shape similarity,
retrieval, and non-rigid correspondence. We phrase the problem as one of alignment
between short sequences of eigenvalues of basic differential operators, which
are constructed upon a scalar function defined on the 3D surfaces. Our method
therefore seeks for a scalar function that entails this alignment. Differently
from existing approaches, we do not require solving for a correspondence between
the query and the target, therefore greatly simplifying the optimization process;
our core technique is also descriptor-free, as it is driven by the geometry of
the two objects as encoded in their operator spectra. We further show that our
spectral alignment algorithm provides a remarkably simple alternative to the recent
shape-from-spectrum reconstruction approaches. For both applications, we demonstrate
improvement over the state-of-the-art either in terms of accuracy or computational
cost.
article_number: '8886146'
article_processing_charge: No
arxiv: 1
author:
- first_name: Arianna
full_name: Rampini, Arianna
last_name: Rampini
- first_name: Irene
full_name: Tallini, Irene
last_name: Tallini
- first_name: Maks
full_name: Ovsjanikov, Maks
last_name: Ovsjanikov
- first_name: Alexander
full_name: Bronstein, Alexander
id: 58f3726e-7cba-11ef-ad8b-e6e8cb3904e6
last_name: Bronstein
orcid: 0000-0001-9699-8730
- first_name: Emanuele
full_name: Rodola, Emanuele
last_name: Rodola
citation:
ama: 'Rampini A, Tallini I, Ovsjanikov M, Bronstein AM, Rodola E. Correspondence-free
region localization for partial shape similarity via Hamiltonian spectrum alignment.
In: 2019 International Conference on 3D Vision (3DV). IEEE; 2019. doi:10.1109/3dv.2019.00014'
apa: 'Rampini, A., Tallini, I., Ovsjanikov, M., Bronstein, A. M., & Rodola,
E. (2019). Correspondence-free region localization for partial shape similarity
via Hamiltonian spectrum alignment. In 2019 International Conference on 3D
Vision (3DV). Quebec City, QC, Canada: IEEE. https://doi.org/10.1109/3dv.2019.00014'
chicago: Rampini, Arianna, Irene Tallini, Maks Ovsjanikov, Alex M. Bronstein, and
Emanuele Rodola. “Correspondence-Free Region Localization for Partial Shape Similarity
via Hamiltonian Spectrum Alignment.” In 2019 International Conference on 3D
Vision (3DV). IEEE, 2019. https://doi.org/10.1109/3dv.2019.00014.
ieee: A. Rampini, I. Tallini, M. Ovsjanikov, A. M. Bronstein, and E. Rodola, “Correspondence-free
region localization for partial shape similarity via Hamiltonian spectrum alignment,”
in 2019 International Conference on 3D Vision (3DV), Quebec City, QC, Canada,
2019.
ista: Rampini A, Tallini I, Ovsjanikov M, Bronstein AM, Rodola E. 2019. Correspondence-free
region localization for partial shape similarity via Hamiltonian spectrum alignment.
2019 International Conference on 3D Vision (3DV). 7th International Conference
on 3D Vision, 8886146.
mla: Rampini, Arianna, et al. “Correspondence-Free Region Localization for Partial
Shape Similarity via Hamiltonian Spectrum Alignment.” 2019 International Conference
on 3D Vision (3DV), 8886146, IEEE, 2019, doi:10.1109/3dv.2019.00014.
short: A. Rampini, I. Tallini, M. Ovsjanikov, A.M. Bronstein, E. Rodola, in:, 2019
International Conference on 3D Vision (3DV), IEEE, 2019.
conference:
end_date: 2019-09-19
location: Quebec City, QC, Canada
name: 7th International Conference on 3D Vision
start_date: 2019-09-16
date_created: 2024-10-08T13:07:51Z
date_published: 2019-10-31T00:00:00Z
date_updated: 2024-12-05T15:49:06Z
day: '31'
doi: 10.1109/3dv.2019.00014
extern: '1'
external_id:
arxiv:
- '1906.06226'
fulldoi: https://doi.org/10.1109/3dv.2019.00014
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.48550/arXiv.1906.06226
month: '10'
oa: 1
oa_version: Preprint
publication: 2019 International Conference on 3D Vision (3DV)
publication_identifier:
eissn:
- 2475-7888
isbn:
- '9781728131320'
publication_status: published
publisher: IEEE
quality_controlled: '1'
scopus_import: '1'
status: public
title: Correspondence-free region localization for partial shape similarity via Hamiltonian
spectrum alignment
type: conference
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
year: '2019'
...