---
_id: '13386'
abstract:
- lang: eng
  text: Azobenzenealkanethiols in self-assembled monolayers (SAMs) on Au(111) exhibit
    reversible trans–cis photoisomerization when diluted with alkanethiol spacers.
    Using these mixed SAMs, we show switching of the linear optical and second-harmonic
    response. The effective switching of these surface optical properties relies on
    a reasonably large cross section and a high photoisomerization yield as well as
    a long lifetime of the metastable cis isomer. We quantified the switching process
    by X-ray absorption spectroscopy. The cross sections for the trans–cis and cis–trans
    photoisomerization with 365 and 455 nm light, respectively, are 1 order of magnitude
    smaller than in solution. In vacuum, the 365 nm photostationary state comprises
    50–74% of the molecules in the cis form, limited by their rapid thermal isomerization
    back to the trans state. In contrast, the 455 nm photostationary state contains
    nearly 100% trans-azobenzene. We determined time constants for the thermal cis–trans
    isomerization of only a few minutes in vacuum and in a dry nitrogen atmosphere
    but of more than 1 day in ambient air. Our results suggest that adventitious water
    adsorbed on the surface of the SAM stabilizes the polar cis configuration of azobenzene
    under ambient conditions. The back reaction rate constants differing by 2 orders
    of magnitude underline the huge influence of the environment and, accordingly,
    its importance when comparing various experiments.
article_processing_charge: No
article_type: original
author:
- first_name: Thomas
  full_name: Moldt, Thomas
  last_name: Moldt
- first_name: Daniel
  full_name: Przyrembel, Daniel
  last_name: Przyrembel
- first_name: Michael
  full_name: Schulze, Michael
  last_name: Schulze
- first_name: Wibke
  full_name: Bronsch, Wibke
  last_name: Bronsch
- first_name: Larissa
  full_name: Boie, Larissa
  last_name: Boie
- first_name: Daniel
  full_name: Brete, Daniel
  last_name: Brete
- first_name: Cornelius
  full_name: Gahl, Cornelius
  last_name: Gahl
- first_name: Rafal
  full_name: Klajn, Rafal
  id: 8e84690e-1e48-11ed-a02b-a1e6fb8bb53b
  last_name: Klajn
- first_name: Petra
  full_name: Tegeder, Petra
  last_name: Tegeder
- first_name: Martin
  full_name: Weinelt, Martin
  last_name: Weinelt
citation:
  ama: Moldt T, Przyrembel D, Schulze M, et al. Differing isomerization kinetics of
    azobenzene-functionalized self-assembled monolayers in ambient air and in vacuum.
    <i>Langmuir</i>. 2016;32(42):10795-10801. doi:<a href="https://doi.org/10.1021/acs.langmuir.6b01690">10.1021/acs.langmuir.6b01690</a>
  apa: Moldt, T., Przyrembel, D., Schulze, M., Bronsch, W., Boie, L., Brete, D., …
    Weinelt, M. (2016). Differing isomerization kinetics of azobenzene-functionalized
    self-assembled monolayers in ambient air and in vacuum. <i>Langmuir</i>. American
    Chemical Society. <a href="https://doi.org/10.1021/acs.langmuir.6b01690">https://doi.org/10.1021/acs.langmuir.6b01690</a>
  chicago: Moldt, Thomas, Daniel Przyrembel, Michael Schulze, Wibke Bronsch, Larissa
    Boie, Daniel Brete, Cornelius Gahl, Rafal Klajn, Petra Tegeder, and Martin Weinelt.
    “Differing Isomerization Kinetics of Azobenzene-Functionalized Self-Assembled
    Monolayers in Ambient Air and in Vacuum.” <i>Langmuir</i>. American Chemical Society,
    2016. <a href="https://doi.org/10.1021/acs.langmuir.6b01690">https://doi.org/10.1021/acs.langmuir.6b01690</a>.
  ieee: T. Moldt <i>et al.</i>, “Differing isomerization kinetics of azobenzene-functionalized
    self-assembled monolayers in ambient air and in vacuum,” <i>Langmuir</i>, vol.
    32, no. 42. American Chemical Society, pp. 10795–10801, 2016.
  ista: Moldt T, Przyrembel D, Schulze M, Bronsch W, Boie L, Brete D, Gahl C, Klajn
    R, Tegeder P, Weinelt M. 2016. Differing isomerization kinetics of azobenzene-functionalized
    self-assembled monolayers in ambient air and in vacuum. Langmuir. 32(42), 10795–10801.
  mla: Moldt, Thomas, et al. “Differing Isomerization Kinetics of Azobenzene-Functionalized
    Self-Assembled Monolayers in Ambient Air and in Vacuum.” <i>Langmuir</i>, vol.
    32, no. 42, American Chemical Society, 2016, pp. 10795–801, doi:<a href="https://doi.org/10.1021/acs.langmuir.6b01690">10.1021/acs.langmuir.6b01690</a>.
  short: T. Moldt, D. Przyrembel, M. Schulze, W. Bronsch, L. Boie, D. Brete, C. Gahl,
    R. Klajn, P. Tegeder, M. Weinelt, Langmuir 32 (2016) 10795–10801.
date_created: 2023-08-01T09:42:37Z
date_published: 2016-10-25T00:00:00Z
date_updated: 2023-08-07T12:27:06Z
day: '25'
doi: 10.1021/acs.langmuir.6b01690
extern: '1'
external_id:
  pmid:
  - '27681851'
intvolume: '        32'
issue: '42'
keyword:
- Electrochemistry
- Spectroscopy
- Surfaces and Interfaces
- Condensed Matter Physics
- General Materials Science
language:
- iso: eng
month: '10'
oa_version: None
page: 10795-10801
pmid: 1
publication: Langmuir
publication_identifier:
  eissn:
  - 1520-5827
  issn:
  - 0743-7463
publication_status: published
publisher: American Chemical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Differing isomerization kinetics of azobenzene-functionalized self-assembled
  monolayers in ambient air and in vacuum
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 32
year: '2016'
...