@article{1436, abstract = {We study the time evolution of a system of N spinless fermions in R3 which interact through a pair potential, e.g., the Coulomb potential. We compare the dynamics given by the solution to Schrödinger's equation with the time-dependent Hartree-Fock approximation, and we give an estimate for the accuracy of this approximation in terms of the kinetic energy of the system. This leads, in turn, to bounds in terms of the initial total energy of the system.}, author = {Bach, Volker and Breteaux, Sébastien and Petrat, Sören P and Pickl, Peter and Tzaneteas, Tim}, journal = {Journal de Mathématiques Pures et Appliquées}, number = {1}, pages = {1 -- 30}, publisher = {Elsevier}, title = {{Kinetic energy estimates for the accuracy of the time-dependent Hartree-Fock approximation with Coulomb interaction}}, doi = {10.1016/j.matpur.2015.09.003}, volume = {105}, year = {2016}, } @inproceedings{1438, abstract = {In this paper, we consider termination of probabilistic programs with real-valued variables. The questions concerned are: (a) qualitative ones that ask (i) whether the program terminates with probability 1 (almost-sure termination) and (ii) whether the expected termination time is finite (finite termination); (b) quantitative ones that ask (i) to approximate the expected termination time (expectation problem) and (ii) to compute a bound B such that the probability to terminate after B steps decreases exponentially (concentration problem). To solve these questions, we utilize the notion of ranking supermartingales which is a powerful approach for proving termination of probabilistic programs. In detail, we focus on algorithmic synthesis of linear ranking-supermartingales over affine probabilistic programs (APP's) with both angelic and demonic non-determinism. An important subclass of APP's is LRAPP which is defined as the class of all APP's over which a linear ranking-supermartingale exists. Our main contributions are as follows. Firstly, we show that the membership problem of LRAPP (i) can be decided in polynomial time for APP's with at most demonic non-determinism, and (ii) is NP-hard and in PSPACE for APP's with angelic non-determinism; moreover, the NP-hardness result holds already for APP's without probability and demonic non-determinism. Secondly, we show that the concentration problem over LRAPP can be solved in the same complexity as for the membership problem of LRAPP. Finally, we show that the expectation problem over LRAPP can be solved in 2EXPTIME and is PSPACE-hard even for APP's without probability and non-determinism (i.e., deterministic programs). Our experimental results demonstrate the effectiveness of our approach to answer the qualitative and quantitative questions over APP's with at most demonic non-determinism.}, author = {Chatterjee, Krishnendu and Fu, Hongfei and Novotny, Petr and Hasheminezhad, Rouzbeh}, location = {St. Petersburg, FL, USA}, pages = {327 -- 342}, publisher = {ACM}, title = {{Algorithmic analysis of qualitative and quantitative termination problems for affine probabilistic programs}}, doi = {10.1145/2837614.2837639}, volume = {20-22}, year = {2016}, } @inproceedings{1439, abstract = {Fault-tolerant distributed algorithms play an important role in many critical/high-availability applications. These algorithms are notoriously difficult to implement correctly, due to asynchronous communication and the occurrence of faults, such as the network dropping messages or computers crashing. We introduce PSYNC, a domain specific language based on the Heard-Of model, which views asynchronous faulty systems as synchronous ones with an adversarial environment that simulates asynchrony and faults by dropping messages. We define a runtime system for PSYNC that efficiently executes on asynchronous networks. We formalize the relation between the runtime system and PSYNC in terms of observational refinement. The high-level lockstep abstraction introduced by PSYNC simplifies the design and implementation of fault-tolerant distributed algorithms and enables automated formal verification. We have implemented an embedding of PSYNC in the SCALA programming language with a runtime system for asynchronous networks. We show the applicability of PSYNC by implementing several important fault-tolerant distributed algorithms and we compare the implementation of consensus algorithms in PSYNC against implementations in other languages in terms of code size, runtime efficiency, and verification.}, author = {Dragoi, Cezara and Henzinger, Thomas A and Zufferey, Damien}, location = {St. Petersburg, FL, USA}, pages = {400 -- 415}, publisher = {ACM}, title = {{PSYNC: A partially synchronous language for fault-tolerant distributed algorithms}}, doi = {10.1145/2837614.2837650}, volume = {20-22}, year = {2016}, } @article{1440, author = {Janovjak, Harald L}, journal = {Structure}, number = {2}, pages = {213 -- 215}, publisher = {Cell Press}, title = {{Light at the end of the protein: Crystal structure of a C-terminal light-sensing domain}}, doi = {10.1016/j.str.2016.01.002}, volume = {24}, year = {2016}, } @article{1446, abstract = {The accuracy of interdisciplinarity measurements is directly related to the quality of the underlying bibliographic data. Existing indicators of interdisciplinarity are not capable of reflecting the inaccuracies introduced by incorrect and incomplete records because correct and complete bibliographic data can rarely be obtained. This is the case for the Rao–Stirling index, which cannot handle references that are not categorized into disciplinary fields. We introduce a method that addresses this problem. It extends the Rao–Stirling index to acknowledge missing data by calculating its interval of uncertainty using computational optimization. The evaluation of our method indicates that the uncertainty interval is not only useful for estimating the inaccuracy of interdisciplinarity measurements, but it also delivers slightly more accurate aggregated interdisciplinarity measurements than the Rao–Stirling index.}, author = {Calatrava Moreno, Maria and Auzinger, Thomas and Werthner, Hannes}, journal = {Scientometrics}, number = {1}, pages = {213 -- 232}, publisher = {Springer}, title = {{On the uncertainty of interdisciplinarity measurements due to incomplete bibliographic data}}, doi = {10.1007/s11192-016-1842-4}, volume = {107}, year = {2016}, } @article{1448, abstract = {We develop a new and systematic method for proving entropic Ricci curvature lower bounds for Markov chains on discrete sets. Using different methods, such bounds have recently been obtained in several examples (e.g., 1-dimensional birth and death chains, product chains, Bernoulli–Laplace models, and random transposition models). However, a general method to obtain discrete Ricci bounds had been lacking. Our method covers all of the examples above. In addition we obtain new Ricci curvature bounds for zero-range processes on the complete graph. The method is inspired by recent work of Caputo, Dai Pra and Posta on discrete functional inequalities.}, author = {Fathi, Max and Maas, Jan}, journal = {The Annals of Applied Probability}, number = {3}, pages = {1774 -- 1806}, publisher = {Institute of Mathematical Statistics}, title = {{Entropic Ricci curvature bounds for discrete interacting systems}}, doi = {10.1214/15-AAP1133}, volume = {26}, year = {2016}, } @article{1794, abstract = {We consider Conditional random fields (CRFs) with pattern-based potentials defined on a chain. In this model the energy of a string (labeling) (Formula presented.) is the sum of terms over intervals [i, j] where each term is non-zero only if the substring (Formula presented.) equals a prespecified pattern w. Such CRFs can be naturally applied to many sequence tagging problems. We present efficient algorithms for the three standard inference tasks in a CRF, namely computing (i) the partition function, (ii) marginals, and (iii) computing the MAP. Their complexities are respectively (Formula presented.), (Formula presented.) and (Formula presented.) where L is the combined length of input patterns, (Formula presented.) is the maximum length of a pattern, and D is the input alphabet. This improves on the previous algorithms of Ye et al. (NIPS, 2009) whose complexities are respectively (Formula presented.), (Formula presented.) and (Formula presented.), where (Formula presented.) is the number of input patterns. In addition, we give an efficient algorithm for sampling, and revisit the case of MAP with non-positive weights.}, author = {Kolmogorov, Vladimir and Takhanov, Rustem}, journal = {Algorithmica}, number = {1}, pages = {17 -- 46}, publisher = {Springer}, title = {{Inference algorithms for pattern-based CRFs on sequence data}}, doi = {10.1007/s00453-015-0017-7}, volume = {76}, year = {2016}, } @article{17952, abstract = {The stability of chemical bonds can be studied experimentally by rupturing single molecule junctions under applied voltage. Here, we compare voltage-induced bond rupture in two Si–Si backbones: one has no alternate conductive pathway whereas the other contains an additional naphthyl pathway in parallel to the Si–Si bond. We show that in contrast to the first system, the second can conduct through the naphthyl group when the Si–Si bond is ruptured using an applied voltage. We investigate this voltage induced Si–Si bond rupture by ab initio density functional theory calculations and molecular dynamics simulations that ultimately demonstrate that the excitation of molecular vibrational modes by tunneling electrons leads to homolytic Si–Si bond rupture.}, author = {Li, Haixing and Kim, Nathaniel T. and Su, Timothy A. and Steigerwald, Michael L. and Nuckolls, Colin and Darancet, Pierre and Leighton, James L. and Venkataraman, Latha}, issn = {1520-5126}, journal = {Journal of the American Chemical Society}, number = {49}, pages = {16159--16164}, publisher = {American Chemical Society}, title = {{Mechanism for Si–Si bond rupture in single molecule junctions}}, doi = {10.1021/jacs.6b10700}, volume = {138}, year = {2016}, } @article{17954, abstract = {Guidelines to predict trends in the electrical conductance of molecules have been developed for the π-system of conjugated systems. Little is known, however, about the conductance of the underlying σ-systems because the π-system usually dominates the transport. Here we study a family of bipyridine-based molecules using STM-break junction experiments and density functional theory transport calculations. We use different lengths and substitution patterns to probe the role of both the σ-system and the π-system in controlling conductance. By exploiting the destructive interference feature found in the π-system of the meta-coupled six-membered aromatic rings, we show that the conductance of the σ-system of a meta-coupled molecule can be probed directly and can even exceed that of its para-coupled analog. These results add to the understanding of the conductance through the chemically hidden σ-electrons.}, author = {Borges, Anders and Fung, E-Dean and Ng, Fay and Venkataraman, Latha and Solomon, Gemma C.}, issn = {1948-7185}, journal = {The Journal of Physical Chemistry Letters}, number = {23}, pages = {4825--4829}, publisher = {American Chemical Society}, title = {{Probing the conductance of the σ-system of bipyridine using destructive interference}}, doi = {10.1021/acs.jpclett.6b02494}, volume = {7}, year = {2016}, } @article{17955, abstract = {The development of molecular components functioning as switches, rectifiers or amplifiers is a great challenge in molecular electronics. A desirable property of such components is functional robustness, meaning that the intrinsic functionality of components must be preserved regardless of the strategy used to integrate them into the final assemblies. Here, this issue is investigated for molecular diodes based on N-phenylbenzamide (NPBA) backbones. The transport properties of molecular junctions derived from NPBA are characterized while varying the nature of the functional groups interfacing the backbone and the gold electrodes required for break-junction measurements. Combining experimental and theoretical methods, it is shown that at low bias (<0.85 V) transport is determined by the same frontier molecular orbital originating from the NPBA core, regardless of the anchoring group employed. The magnitude of rectification, however, is strongly dependent on the strength of the electronic coupling at the gold–NPBA interface and on the spatial distribution of the local density of states of the dominant transport channel of the molecular junction.}, author = {Koepf, Matthieu and Koenigsmann, Christopher and Ding, Wendu and Batra, Arunbah and Negre, Christian F. A. and Venkataraman, Latha and Brudvig, Gary W. and Batista, Victor S. and Schmuttenmaer, Charles A. and Crabtree, Robert H.}, issn = {2040-3372}, journal = {Nanoscale}, number = {36}, pages = {16357--16362}, publisher = {Royal Society of Chemistry}, title = {{Controlling the rectification properties of molecular junctions through molecule–electrode coupling}}, doi = {10.1039/c6nr04830g}, volume = {8}, year = {2016}, } @article{17956, abstract = {A highly conducting electronic contact between a strained disilane and Au is demonstrated through scanning tunneling microscope-based single-molecule measurements. Conformationally locked cis diastereomers of bis(sulfide)-anchor-equipped 1,2-disilaacenaphthenes readily form high-conducting junctions in which the two sulfide anchors bind in a bipodal fashion to one gold electrode, providing enough stability for a stable electrical contact between the Si–Si σ bond and the other electrode.}, author = {Kim, Nathaniel T. and Li, Haixing and Venkataraman, Latha and Leighton, James L.}, issn = {1520-5126}, journal = {Journal of the American Chemical Society}, number = {36}, pages = {11505--11508}, publisher = {American Chemical Society}, title = {{High-conductance pathways in ring-strained disilanes by qay of direct σ-Si–Si to Au coordination}}, doi = {10.1021/jacs.6b07825}, volume = {138}, year = {2016}, } @article{17957, abstract = {While the single-molecule conductance properties of π-conjugated and σ-conjugated systems have been well-studied, little is known regarding the conductance properties of mixed σ–π backbone wires and the factors that control their transport properties. Here we utilize a scanning tunneling microscope-based break-junction technique to study a series of molecular wires with π–σ–π backbone structures, where the π-moiety is an electrode-binding thioanisole ring and the σ-moiety is a triatomic α–β–α chain composed of C, Si, or Ge atoms. We find that the sequence and composition of group 14 atoms in the α–β–α chain dictates whether electronic communication between the aryl rings is enhanced or suppressed. Placing heavy atoms at the α-position decreases conductance, whereas placing them at the β-position increases conductance: for example, the C–Ge–C sequence is over 20 times more conductive than the Ge–C–Ge sequence. Density functional theory calculations reveal that these conductance trends arise from periodic trends (i.e., atomic size, polarizability, and electronegativity) that differ from C to Si to Ge. The periodic trends that control molecular conductance here are the same ones that give rise to the α and β silicon effects from physical organic chemistry. These findings outline a new molecular design concept for tuning conductance in single-molecule electrical devices.}, author = {Su, Timothy A. and Li, Haixing and Klausen, Rebekka S. and Widawsky, Jonathan R. and Batra, Arunabh and Steigerwald, Michael L. and Venkataraman, Latha and Nuckolls, Colin}, issn = {1520-5126}, journal = {Journal of the American Chemical Society}, number = {24}, pages = {7791--7795}, publisher = {American Chemical Society}, title = {{Tuning conductance in π–σ–π single-molecule wires}}, doi = {10.1021/jacs.6b04394}, volume = {138}, year = {2016}, } @article{17958, abstract = {Charge transport phenomena in single-molecule junctions are often dominated by tunneling, with a transmission function dictating the probability that electrons or holes tunnel through the junction. Here, we present a new and simple technique for measuring the transmission functions of molecular junctions in the coherent tunneling limit, over an energy range of 1.5 eV around the Fermi energy. We create molecular junctions in an ionic environment with electrodes having different exposed areas, which results in the formation of electric double layers of dissimilar density on the two electrodes. This allows us to electrostatically shift the molecular resonance relative to the junction Fermi levels in a manner that depends on the sign of the applied bias, enabling us to map out the junction’s transmission function and determine the dominant orbital for charge transport in the molecular junction. We demonstrate this technique using two groups of molecules: one group having molecular resonance energies relatively far from EF and one group having molecular resonance energies within the accessible bias window. Our results compare well with previous electrochemical gating data and with transmission functions computed from first principles. Furthermore, with the second group of molecules, we are able to examine the behavior of a molecular junction as a resonance shifts into the bias window. This work provides a new, experimentally simple route for exploring the fundamentals of charge transport at the nanoscale.}, author = {Capozzi, Brian and Low, Jonathan Z. and Xia, Jianlong and Liu, Zhen-Fei and Neaton, Jeffrey B. and Campos, Luis M. and Venkataraman, Latha}, issn = {1530-6992}, journal = {Nano Letters}, number = {6}, pages = {3949--3954}, publisher = {American Chemical Society}, title = {{Mapping the transmission functions of single-molecule junctions}}, doi = {10.1021/acs.nanolett.6b01592}, volume = {16}, year = {2016}, } @article{17959, abstract = {Single-molecule conductance measurements have focused primarily on organic molecular systems. Here, we carry out scanning tunneling microscope-based break-junction measurements on a series of metal chalcogenide Co6Se8 clusters capped with conducting ligands of varying lengths. We compare these measurements with those of individual free ligands and find that the conductance of these clusters and the free ligands have different decay constants with increasing ligand length. We also show, through measurements in two different solvents, 1-bromonaphthalene and 1,2,4-trichlorobenzene, that the conductance decay of the clusters depends on the solvent environment. We discuss several mechanisms to explain our observations.}, author = {Choi, Bonnie and Capozzi, Brian and Ahn, Seokhoon and Turkiewicz, Ari and Lovat, Giacomo and Nuckolls, Colin and Steigerwald, Michael L. and Venkataraman, Latha and Roy, Xavier}, issn = {2041-6539}, journal = {Chemical Science}, number = {4}, pages = {2701--2705}, publisher = {Royal Society of Chemistry}, title = {{Solvent-dependent conductance decay constants in single cluster junctions}}, doi = {10.1039/c5sc02595h}, volume = {7}, year = {2016}, } @article{17960, abstract = {Over the past 10 years, there has been tremendous progress in the measurement, modeling and understanding of structure–function relationships in single molecule junctions. Numerous research groups have addressed significant scientific questions, directed both to conductance phenomena at the single molecule level and to the fundamental chemistry that controls junction functionality. Many different functionalities have been demonstrated, including single-molecule diodes, optically and mechanically activated switches, and, significantly, physical phenomena with no classical analogues, such as those based on quantum interference effects. Experimental techniques for reliable and reproducible single molecule junction formation and characterization have led to this progress. In particular, the scanning tunneling microscope based break-junction (STM-BJ) technique has enabled rapid, sequential measurement of large numbers of nanoscale junctions allowing a statistical analysis to readily distinguish reproducible characteristics. Harnessing fundamental link chemistry has provided the necessary chemical control over junction formation, enabling measurements that revealed clear relationships between molecular structure and conductance characteristics. Such link groups (amines, methylsuflides, pyridines, etc.) maintain a stable lone pair configuration that selectively bonds to specific, undercoordinated transition metal atoms available following rupture of a metal point contact in the STM-BJ experiments. This basic chemical principle rationalizes the observation of highly reproducible conductance signatures. Subsequently, the method has been extended to probe a variety of physical phenomena ranging from basic I–V characteristics to more complex properties such as thermopower and electrochemical response. By adapting the technique to a conducting cantilever atomic force microscope (AFM-BJ), simultaneous measurement of the mechanical characteristics of nanoscale junctions as they are pulled apart has given complementary information such as the stiffness and rupture force of the molecule-metal link bond. Overall, while the BJ technique does not produce a single molecule circuit for practical applications, it has proved remarkably versatile for fundamental studies. Measured data and analysis have been combined with atomic-scale theory and calculations, typically performed for representative junction structures, to provide fundamental physical understanding of structure–function relationships. This Account integrates across an extensive series of our specific nanoscale junction studies which were carried out with the STM- and AFM-BJ techniques and supported by theoretical analysis and density functional theory based calculations, with emphasis on the physical characteristics of the measurement process and the rich data sets that emerge. Several examples illustrate the impact of measured trends based on the most probable values for key characteristics (obtained from ensembles of order 1000–10 000 individual junctions) to build a solid picture of conductance phenomena as well as attributes of the link bond chemistry. The key forward-looking question posed here is the extent to which the full data sets represented by the individual trajectories can be analyzed to address structure–function questions at the level of individual junctions. Initial progress toward physical modeling of conductance of individual junctions indicates trends consistent with physical junction structures. Analysis of junction mechanics reveals a scaling procedure that collapses existing data onto a universal force–extension curve. This research directed to understanding the distribution of structures and physical characteristics addresses fundamental questions concerning the interplay between chemical control and stochastically driven diversity.}, author = {Hybertsen, Mark S. and Venkataraman, Latha}, issn = {1520-4898}, journal = {Accounts of Chemical Research}, number = {3}, pages = {452--460}, publisher = {American Chemical Society}, title = {{Structure–property relationships in atomic-scale junctions: Histograms and beyond}}, doi = {10.1021/acs.accounts.6b00004}, volume = {49}, year = {2016}, } @article{17961, abstract = {The field of single-molecule electronics harnesses expertise from engineering, physics and chemistry to realize circuit elements at the limit of miniaturization; it is a subfield of nanoelectronics in which the electronic components are single molecules. In this Review, we survey the field from a chemical perspective and discuss the structure–property relationships of the three components that form a single-molecule junction: the anchor, the electrode and the molecular bridge. The spatial orientation and electronic coupling between each component profoundly affect the conductance properties and functions of the single-molecule device. We describe the design principles of the anchor group, the influence of the electronic configuration of the electrode and the effect of manipulating the structure of the molecular backbone and of its substituent groups. We discuss single-molecule conductance switches as well as the phenomenon of quantum interference and then trace their fundamental roots back to chemical principles.}, author = {Su, Timothy A. and Neupane, Madhav and Steigerwald, Michael L. and Venkataraman, Latha and Nuckolls, Colin}, issn = {2058-8437}, journal = {Nature Reviews Materials}, number = {3}, publisher = {Springer Nature}, title = {{Chemical principles of single-molecule electronics}}, doi = {10.1038/natrevmats.2016.2}, volume = {1}, year = {2016}, } @article{17962, abstract = {We examine structure–function relationships in a series of N-phenylbenzamide (NPBA) derivatives by using computational modeling to identify molecular structures that exhibit both rectification and good conductance together with experimental studies of bias-dependent single molecule conductance and rectification behavior using the scanning tunneling microscopy break-junction technique. From a large number of computationally screened molecular diode structures, we have identified NPBA as a promising candidate, relative to the other structures that were screened. We demonstrate experimentally that conductance and rectification are both enhanced by functionalization of the NPBA 4-carboxamido-aniline moiety with electron donating methoxy groups, and are strongly correlated with the energy of the conducting frontier orbital relative to the Fermi level of the gold leads used in break-junction experiments.}, author = {Koenigsmann, Christopher and Ding, Wendu and Koepf, Matthieu and Batra, Arunabh and Venkataraman, Latha and Negre, Christian F. A. and Brudvig, Gary W. and Crabtree, Robert H. and Batista, Victor S. and Schmuttenmaer, Charles A.}, issn = {1369-9261}, journal = {New Journal of Chemistry}, number = {9}, pages = {7373--7378}, publisher = {Royal Society of Chemistry}, title = {{Structure–function relationships in single molecule rectification by N-phenylbenzamide derivatives}}, doi = {10.1039/c6nj00870d}, volume = {40}, year = {2016}, } @article{17963, abstract = {Here we examine the impact of ring conformation on the charge transport characteristics of cyclic pentasilane structures bound to gold electrodes in single molecule junctions. We investigate the conductance properties of alkylated cyclopentasilane cis and trans stereoisomers substituted in the 1,3-position with methylthiomethyl electrode binding groups using both the scanning tunneling microscope-based break junction technique and density functional theory based ab initio calculations. In contrast with the linear ones, these cyclic silanes yield lower conductance values; calculations reveal that the constrained dihedral geometries occurring within the ring are suboptimal for σ-orbital delocalization, and therefore, conductance. Theoretical calculations reproduce the measured conductance trends for both cis and trans isomers and find several distinct conformations that are likely to form stable molecular junctions at room temperature. Due to the weakened σ-conjugation in the molecule, through-space interactions are found to contribute significantly to the conductance. This manuscript details the vast conformational flexibility in cyclopentasilanes and the tremendous impact it has on controlling conductance.}, author = {Li, Haixing and Garner, Marc H. and Shangguan, Zhichun and Zheng, Qianwen and Su, Timothy A. and Neupane, Madhav and Li, Panpan and Velian, Alexandra and Steigerwald, Michael L. and Xiao, Shengxiong and Nuckolls, Colin and Solomon, Gemma C. and Venkataraman, Latha}, issn = {2041-6539}, journal = {Chemical Science}, number = {9}, pages = {5657--5662}, publisher = {Royal Society of Chemistry}, title = {{Conformations of cyclopentasilane stereoisomers control molecular junction conductance}}, doi = {10.1039/c6sc01360k}, volume = {7}, year = {2016}, } @article{17964, abstract = {Charge transfer rates at metal/organic interfaces affect the efficiencies of devices for organic based electronics and photovoltaics. A quantitative study of electron transfer rates, which take place on the femtosecond timescale, is often difficult, especially since in most systems the molecular adsorption geometry is unknown. Here, we use X-ray resonant photoemission spectroscopy to measure ultrafast charge transfer rates across pyridine/Au(111) interfaces while also controlling the molecular orientation on the metal. We demonstrate that a bi-directional charge transfer across the molecule/metal interface is enabled upon creation of a core-exciton on the molecule with a rate that has a strong dependence on the molecular adsorption angle. Through density functional theory calculations, we show that the alignment of molecular levels relative to the metal Fermi level is dramatically altered when a core-hole is created on the molecule, allowing the lowest unoccupied molecular orbital to fall partially below the metal Fermi level. We also calculate charge transfer rates as a function of molecular adsorption geometry and find a trend that agrees with the experiment. These findings thus give insight into the charge transfer dynamics of a photo-excited molecule on a metal surface.}, author = {Cvetko, Dean and Fratesi, Guido and Kladnik, Gregor and Cossaro, Albano and Brivio, Gian Paolo and Venkataraman, Latha and Morgante, Alberto}, issn = {1463-9084}, journal = {Physical Chemistry Chemical Physics}, number = {32}, pages = {22140--22145}, publisher = {Royal Society of Chemistry}, title = {{Ultrafast electron injection into photo-excited organic molecules}}, doi = {10.1039/c6cp04099c}, volume = {18}, year = {2016}, } @inbook{18328, abstract = {We present a novel sparse modeling approach to non-rigid shape matching using only the ability to detect repeatable regions. As the input to our algorithm, we are given only two sets of regions in two shapes; no descriptors are provided so the correspondence between the regions is not know, nor do we know how many regions correspond in the two shapes. We show that even with such scarce information, it is possible to establish very accurate correspondence between the shapes by using methods from the field of sparse modeling, being this, the first non-trivial use of sparse models in shape correspondence. We formulate the problem of permuted sparse coding, in which we solve simultaneously for an unknown permutation ordering the regions on two shapes and for an unknown correspondence in functional representation. We also propose a robust variant capable of handling incomplete matches. Numerically, the problem is solved efficiently by alternating the solution of a linear assignment and a sparse coding problem. The proposed methods are evaluated qualitatively and quantitatively on standard benchmarks containing both synthetic and scanned objects.}, author = {Pokrass, Jonathan and Bronstein, Alexander and Bronstein, Michael M. and Sprechmann, Pablo and Sapiro, Guillermo}, booktitle = {Perspectives in Shape Analysis}, editor = {Breuß, Michael and Bruckstein, Alfred and Maragos, Petros and Wuhrer, Stefanie}, isbn = {9783319247243}, issn = {2197-666X}, pages = {211--230}, publisher = {Springer International Publishing}, title = {{Sparse Models for Intrinsic Shape Correspondence}}, doi = {10.1007/978-3-319-24726-7_10}, year = {2016}, }