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Yao J, Park Y, Shi W, Chen S, Ho W. Origin of photoinduced DC current and two-level population dynamics in a single molecule. SCIENCE ADVANCES 2024; 10:eadk9211. [PMID: 38295170 PMCID: PMC10830102 DOI: 10.1126/sciadv.adk9211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 01/02/2024] [Indexed: 02/02/2024]
Abstract
Studying the photoinduced changes of materials with atomic-scale spatial resolution can provide a fundamental understanding of light-matter interaction. A long-standing impediment has been the detrimental thermal effects on the stability of the tunneling gap from intensity-modulated laser irradiation of the scanning tunneling microscope junction. Photoinduced DC current transduces photons to an electric current and is widely applied in optoelectronics as switches and signal transmission. Our results revealed the origin of the light-induced DC current and related it to the two-level population dynamics and related nonlinearity in the conductance of a single molecule. Here, we compensated for the near-visible laser-induced thermal effects to demonstrate photoinduced DC current spectroscopy and microscopy and to observe the persistent photoconductivity of a two-level pyrrolidine molecule. The methodology can be generally applied to the coupling of light to scan probes to investigate light-matter interactions at the atomic scale.
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Affiliation(s)
- Jiang Yao
- Department of Physics and Astronomy, University of California, Irvine, Irvine, CA 92697-4575, USA
| | - Youngwook Park
- Department of Physics and Astronomy, University of California, Irvine, Irvine, CA 92697-4575, USA
| | - Wenlu Shi
- Department of Physics and Astronomy, University of California, Irvine, Irvine, CA 92697-4575, USA
| | - Siyu Chen
- Department of Physics and Astronomy, University of California, Irvine, Irvine, CA 92697-4575, USA
| | - W. Ho
- Department of Physics and Astronomy, University of California, Irvine, Irvine, CA 92697-4575, USA
- Department of Chemistry, University of California, Irvine, Irvine, CA 92697-2025, USA
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2
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Wang H, Lee D, Cao Y, Bi X, Du J, Miao K, Wei L. Bond-selective fluorescence imaging with single-molecule sensitivity. NATURE PHOTONICS 2023; 17:846-855. [PMID: 38162388 PMCID: PMC10756635 DOI: 10.1038/s41566-023-01243-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 05/25/2023] [Indexed: 01/03/2024]
Abstract
Bioimaging harnessing optical contrasts and chemical specificity is of vital importance in probing complex biology. Vibrational spectroscopy based on mid-infrared (mid-IR) excitation can reveal rich chemical information about molecular distributions. However, its full potential for bioimaging is hindered by the achievable sensitivity. Here, we report bond selective fluorescence-detected infrared-excited (BonFIRE) spectral microscopy. BonFIRE employs two-photon excitation in the mid-IR and near-IR to upconvert vibrational excitations to electronic states for fluorescence detection, thus encoding vibrational information into fluorescence. The system utilizes tuneable narrowband picosecond pulses to ensure high sensitivity, biocompatibility, and robustness for bond-selective biological interrogations over a wide spectrum of reporter molecules. We demonstrate BonFIRE spectral imaging in both fingerprint and cell-silent spectroscopic windows with single-molecule sensitivity for common fluorescent dyes. We then demonstrate BonFIRE imaging on various intracellular targets in fixed and live cells, neurons, and tissues, with promises for further vibrational multiplexing. For dynamic bioanalysis in living systems, we implement a high-frequency modulation scheme and demonstrate time-lapse BonFIRE microscopy of live HeLa cells. We expect BonFIRE to expand the bioimaging toolbox by providing a new level of bond-specific vibrational information and facilitate functional imaging and sensing for biological investigations.
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Affiliation(s)
- Haomin Wang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Dongkwan Lee
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Yulu Cao
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Xiaotian Bi
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Jiajun Du
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Kun Miao
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Lu Wei
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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3
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Sarkar S, Au-Yeung KH, Kühne T, Waentig A, Ryndyk DA, Heine T, Cuniberti G, Feng X, Moresco F. Adsorption and reversible conformational change of a thiophene based molecule on Au(111). Sci Rep 2023; 13:10627. [PMID: 37391525 DOI: 10.1038/s41598-023-37661-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 06/25/2023] [Indexed: 07/02/2023] Open
Abstract
We present a low temperature scanning tunneling microscope investigation of a prochiral thiophene-based molecule that self-assembles forming islands with different domains on the Au(111) surface. In the domains, two different conformations of the single molecule are observed, depending on a slight rotation of two adjacent bromothiophene groups. Using voltage pulses from the tip, single molecules can be switched between the two conformations. The electronic states have been measured with scanning tunneling spectroscopy, showing that the electronic resonances are mainly localized at the same positions in both conformations. Density-functional theory calculations support the experimental results. Furthermore, we observe that on Ag(111), only one configuration is present and therefore the switching effect is suppressed.
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Affiliation(s)
- Suchetana Sarkar
- Center for Advancing Electronics Dresden, TU Dresden, 01062, Dresden, Germany
| | - Kwan Ho Au-Yeung
- Center for Advancing Electronics Dresden, TU Dresden, 01062, Dresden, Germany
| | - Tim Kühne
- Center for Advancing Electronics Dresden, TU Dresden, 01062, Dresden, Germany
| | - Albrecht Waentig
- Center for Advancing Electronics Dresden, TU Dresden, 01062, Dresden, Germany
- Chair of Molecular Functional Materials and Faculty of Chemistry and Food Chemistry, TU Dresden, 01062, Dresden, Germany
| | - Dmitry A Ryndyk
- Theoretical Chemistry, TU Dresden, 01062, Dresden, Germany
- Institute for Materials Science, TU Dresden, 01062, Dresden, Germany
| | - Thomas Heine
- Theoretical Chemistry, TU Dresden, 01062, Dresden, Germany
| | | | - Xinliang Feng
- Center for Advancing Electronics Dresden, TU Dresden, 01062, Dresden, Germany
- Chair of Molecular Functional Materials and Faculty of Chemistry and Food Chemistry, TU Dresden, 01062, Dresden, Germany
| | - Francesca Moresco
- Center for Advancing Electronics Dresden, TU Dresden, 01062, Dresden, Germany.
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4
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Choi B, Jeong G, Shin HH, Kim ZH. Molecular vibrational imaging at nanoscale. J Chem Phys 2022; 156:160902. [PMID: 35490022 DOI: 10.1063/5.0082747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The demand to visualize the spatial distribution of chemical species based on vibrational spectra is rapidly increasing. Driven by such a need, various Raman and infrared spectro-microscopies with a nanometric spatial resolution have been developed over the last two decades. Despite rapid progress, a large gap still exists between the general needs and what these techniques can achieve. This Perspective highlights the key challenges and recent breakthroughs of the two vibrational nano-imaging techniques, scattering-type scanning near-field optical microscopy and tip-enhanced Raman scattering.
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Affiliation(s)
- Boogeon Choi
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Gyouil Jeong
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Hyun-Hang Shin
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Zee Hwan Kim
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
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5
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Suzuki S. Development of a Novel Surface Elemental Analysis Methodology: X-ray-Aided Noncontact Atomic Force Microscopy (XANAM). BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2015. [DOI: 10.1246/bcsj.20140286] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Shushi Suzuki
- Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University
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6
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Burema SR, Seufert K, Auwärter W, Barth JV, Bocquet ML. Probing nitrosyl ligation of surface-confined metalloporphyrins by inelastic electron tunneling spectroscopy. ACS NANO 2013; 7:5273-81. [PMID: 23718257 PMCID: PMC3833350 DOI: 10.1021/nn4010582] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Complexes obtained by the ligation of nitric oxide (NO) to metalloporphyrins represent important model systems with biological relevance. Herein we report a molecular-level investigation of surface-confined cobalt tetraphenyl porphyrin (Co-TPP) species and their interaction with NO under ultrahigh vacuum conditions. It is demonstrated that individual NO adducts can be desorbed using the atomically sharp tip of a scanning tunneling microscope, whereby a writing process is implemented for fully saturated regular metalloporphyrin arrays. The low-energy vibrational characteristics of individual Co-TPP-nitrosyl complexes probed by inelastic electron tunneling spectroscopy (IETS) reveal a prominent signature at an energy of ~/=31 meV. Using density functional theory-based IETS simulations-the first to be performed on such an extensive interfacial nanosystem-we succeed to reproduce the low-frequency spectrum for the NO-ligated complex and explain the absence of IETS activity for bare Co-TPP. Moreover, we can conclusively assign the IETS peak of NO-Co-TPP to a unique vibration mode involving the NO complexation site, namely, the in-plane Co-N-O rocking mode. In addition, we verify that the propensity rules previously designed on small aromatic systems and molecular fragments hold true for a metal-organic entity. This work notably permits one to envisage IETS spectroscopy as a sensitive tool to chemically characterize hybrid interfaces formed by complex metal-organic units and gaseous adducts.
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Affiliation(s)
- Shiri R. Burema
- Laboratoire de Chimie, CNRS UMR 5182, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, 69364 CEDEX07 Lyon, France
| | - Knud Seufert
- Physik Department E20, Technische Universität München, James-Franck Str. D-85748 Garching, Germany
| | - Willi Auwärter
- Physik Department E20, Technische Universität München, James-Franck Str. D-85748 Garching, Germany
| | - Johannes V. Barth
- Physik Department E20, Technische Universität München, James-Franck Str. D-85748 Garching, Germany
| | - Marie-Laure Bocquet
- Laboratoire de Chimie, CNRS UMR 5182, Ecole Normale Supérieure de Lyon, 46 Allée d’Italie, 69364 CEDEX07 Lyon, France
- Address correspondence to
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7
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Lechner BAJ, Sacchi M, Jardine AP, Hedgeland H, Allison W, Ellis J, Jenkins SJ, Dastoor PC, Hinch BJ. Jumping, Rotating, and Flapping: The Atomic-Scale Motion of Thiophene on Cu(111). J Phys Chem Lett 2013; 4:1953-1958. [PMID: 26283133 DOI: 10.1021/jz400639c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Self-assembled monolayers of sulfur-containing heterocycles and linear oligomers containing thiophene groups have been widely employed in organic electronic applications. Here, we investigate the dynamics of isolated thiophene molecules on Cu(111) by combining helium spin-echo (HeSE) spectroscopy with density functional theory calculations. We show that the thiophene/Cu(111) system displays a rich array of aperiodic dynamical phenomena that include jump diffusion between adjacent atop sites over a 59-62 meV barrier and activated rotation around a sulfur-copper anchor, two processes that have been observed previously for related systems. In addition, we present experimental evidence for a new, weakly activated process, the flapping of the molecular ring. Repulsive inter-adsorbate interactions and an exceptionally high friction coefficient of 5 ± 2 ps(-1) are also observed. These experiments demonstrate the versatility of the HeSE technique, and the quantitative information extracted in a detailed analysis provides an ideal benchmark for state-of-the-art theoretical techniques including nonlocal adsorbate-substrate interactions.
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Affiliation(s)
- Barbara A J Lechner
- †Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Marco Sacchi
- ‡Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Andrew P Jardine
- †Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Holly Hedgeland
- †Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - William Allison
- †Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - John Ellis
- †Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Stephen J Jenkins
- ‡Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Paul C Dastoor
- §Centre for Organic Electronics, University of Newcastle, Callaghan NSW 2308, Australia
| | - B J Hinch
- ∥Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
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8
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Burema SR, Bocquet ML. A sum rule for inelastic electron tunneling spectroscopy: an ab initio study of a donor (TTF) and acceptors (TCNE, TCNQ and DCNQI) parallelly oriented on Cu(100). Phys Chem Chem Phys 2013; 15:16111-9. [DOI: 10.1039/c3cp53049c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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9
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Burema SR, Bocquet ML. Resonance Charges to Encode Selection Rules in Inelastic Electron Tunneling Spectroscopy. J Phys Chem Lett 2012; 3:3007-3011. [PMID: 26292242 DOI: 10.1021/jz3012832] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
From extensive simulations of a set of covalently grafted phenyl derivatives onto Cu(111), we derive a simplistic rule that selectively predicts the onset of stretching vibrations in inelastic electron tunneling spectroscopy (IETS) with the scanning tunneling microscope. Indeed the rise (extinction) of the highest-frequency modes is found to correlate to the accumulation (depletion) of π electron density at the metal-organic contact point. This π electron density can be fine-tuned by the usage of (de) activating aromatic substituent at different ring positions. This finding provides a simple analysis tool that can be used to reveal structural characteristics on the atomic scale by IETS.
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Affiliation(s)
- Shiri R Burema
- Ecole Normale Supérieure de Lyon, Laboratoire de Chimie, CNRS UMR 5182, 46 Allée d'Italie, 69364 CEDEX07 Lyon, France
| | - Marie-Laure Bocquet
- Ecole Normale Supérieure de Lyon, Laboratoire de Chimie, CNRS UMR 5182, 46 Allée d'Italie, 69364 CEDEX07 Lyon, France
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10
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SEIDEMAN TAMAR, GUO HONG. QUANTUM TRANSPORT AND CURRENT-TRIGGERED DYNAMICS IN MOLECULAR TUNNEL JUNCTIONS. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2011. [DOI: 10.1142/s0219633603000616] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The modelling of nanoelectronic systems has been the topic of ever increasing activity for nearly two decades. Yet, new questions, challenges and opportunities continue to emerge. In this article we review theoretical and numerical work on two new developments in the theory of molecular-scale electronics. First we review a density functional theory analysis within the Keldysh non-equilibrium Green function formalism to predict nonlinear charge transport properties of nanoelectronic devices. Next we review a recently developed quantum mechanical formalism of current-triggered nuclear dynamics. Finally we combine these theories to describe from first principles the inelastic current and the consequent molecular dynamics in molecular heterojunctions.
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Affiliation(s)
- TAMAR SEIDEMAN
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL. 60208-3113, USA
| | - HONG GUO
- Center for the Physics of Materials & Department of Physics, McGill University, Montreal, PQ, Canada H3A 2T8, Canada
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11
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Kunitski M, Riehn C, Matylitsky VV, Tarakeshwar P, Brutschy B. Pseudorotation in pyrrolidine: rotational coherence spectroscopy and ab initio calculations of a large amplitude intramolecular motion. Phys Chem Chem Phys 2009; 12:72-81. [PMID: 20024446 DOI: 10.1039/b917362e] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Pseudorotation in the pyrrolidine molecule was studied by means of femtosecond degenerate four-wave mixing spectroscopy both in the gas cell at room temperature and under supersonic expansion. The experimental observations were reproduced by a fitted simulation based on a one-dimensional model for pseudorotation. Of the two conformers, axial and equatorial, the latter was found to be stabilized by about 29 +/- 10 cm(-1) relative to the former one. The barrier for pseudorotation was determined to be 220 +/- 20 cm(-1). In addition, quantum chemical calculations of the pseudorotational path of pyrrolidine were performed using the synchronous transit-guided quasi-Newton method at the MP2 and B3LYP levels of theory. Subsequent CCSD(T) calculations yield the energy preference of the equatorial conformer and the barrier for pseudorotation to be 17 and 284 cm(-1), respectively.
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Affiliation(s)
- Maksim Kunitski
- Institut für Physikalische und Theoretische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Strasse 760438 Frankfurt am Main, Germany
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12
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Adsorption changes of cyclohexyl isothiocyanate on gold surfaces. J Colloid Interface Sci 2009; 336:648-53. [DOI: 10.1016/j.jcis.2009.04.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2009] [Revised: 03/12/2009] [Accepted: 04/08/2009] [Indexed: 11/19/2022]
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13
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Lee NS, Choi WS, Shin HK, Qian DJ, Kwon YS. A study on conformational changes by electron charges in viologen single molecules by using STM. Ultramicroscopy 2008; 108:1101-5. [DOI: 10.1016/j.ultramic.2008.04.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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14
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Hahn JR, Ho W. Imaging and vibrational spectroscopy of single pyridine molecules on Ag(110) using a low-temperature scanning tunneling microscope. J Chem Phys 2006; 124:204708. [PMID: 16774365 DOI: 10.1063/1.2200350] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A scanning tunneling microscope (STM) was used to extract the images of single, isolated pyridine molecules adsorbed on Ag(110) and to record their vibrational spectrum at 13 K. On the STM image, the pyridine molecule appears as an elongated protrusion along the [001] direction on top of a silver atom, indicating that it is bonded through its nitrogen lone pair electrons. STM inelastic electron tunneling spectroscopy of the adsorbed pyridine revealed C-D and C-H stretch modes at 282 and 378 meV, respectively.
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Affiliation(s)
- J R Hahn
- Department of Chemistry, Chonbuk National University, Jeonju 561-756, Korea.
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15
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Maddox JB, Harbola U, Liu N, Silien C, Ho W, Bazan GC, Mukamel S. Simulation of Single Molecule Inelastic Electron Tunneling Signals in Paraphenylene−Vinylene Oligomers and Distyrylbenzene[2.2]paracyclophanes. J Phys Chem A 2006; 110:6329-38. [PMID: 16686469 DOI: 10.1021/jp061590b] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Inelastic resonances in the electron tunneling spectra of several conjugated molecules are simulated using the nonequilibrium Greens function formalism. The vibrational modes that strongly couple to the electronic current are different from the infrared and Raman active modes. Spatially resolved inelastic electron tunneling (IET) intensities are predicted. The simulated IET intensities for a large distyrylbenzene paracyclophane molecule are in qualitative agreement with recent experimental results.
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Affiliation(s)
- Jeremy B Maddox
- Department of Chemistry, University of California, Irvine, California 92697, USA
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16
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Haiss W, van Zalinge H, Bethell D, Ulstrup J, Schiffrin DJ, Nichols RJ. Thermal gating of the single molecule conductance of alkanedithiols. Faraday Discuss 2006; 131:253-64; discussion 307-24. [PMID: 16512376 DOI: 10.1039/b507520n] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The temperature dependence of the single molecule conductance (SMC) of alpha,omega-alkanedithiols has been investigated using a scanning tunnelling microscopy (STM) method. This is based on trapping molecules between a gold STM tip and a gold substrate and measuring directly the current across the molecule under different applied potentials. A pronounced temperature dependence of the conductance, which scales logarithmically with T(1), is observed in the temperature range between 293 and 353 K. It is proposed the origin of this dependence is the change in distribution between molecular conformers rather than changes in either the conduction mechanism or the electronic structure of molecule. For alkanedithiols the time averaged conformer distribution shifts to less elongated conformers at higher temperatures thus giving rise to higher conductance across the molecular bridges. This is analysed by first calculating energy differences between different conformers and then calculating their partition distribution. A simple tunnelling model is then used to calculate the temperature dependent conductance based on the conformer distribution. These findings demonstrate that charge transport through single organic molecules at ambient temperatures is a subtle and highly dynamic process that cannot be described by analysing only one molecular conformation corresponding to the lowest energy geometry of the molecule.
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Affiliation(s)
- Wolfgang Haiss
- Centre for Nonoscale Science, Chemistry Department, University of Liverpool, Liverpool L69 7ZD, UK
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17
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Scanning tunneling microscopy single atom/molecule manipulation and its application to nanoscience and technology. ACTA ACUST UNITED AC 2005. [DOI: 10.1116/1.1990161] [Citation(s) in RCA: 136] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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18
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Gómez-Zavaglia A, Fausto R. Self-Aggregation in Pyrrole: Matrix Isolation, Solid State Infrared Spectroscopy, and DFT Study. J Phys Chem A 2004. [DOI: 10.1021/jp048118f] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrea Gómez-Zavaglia
- Department of Chemistry, University of Coimbra, P-3004-535, Portugal, and Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, RA-1113, Argentina
| | - Rui Fausto
- Department of Chemistry, University of Coimbra, P-3004-535, Portugal, and Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, RA-1113, Argentina
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20
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Kim Y, Komeda T, Kawai M. Single-molecule reaction and characterization by vibrational excitation. PHYSICAL REVIEW LETTERS 2002; 89:126104. [PMID: 12225106 DOI: 10.1103/physrevlett.89.126104] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2002] [Indexed: 05/23/2023]
Abstract
Controlled chemical reaction of single trans-2-butene molecules on the Pd(110) surface was realized by dosing tunneling electrons from the tip of a scanning tunneling microscope at 4.7 K. The reaction product was identified as a 1,3-butadiene molecule by inelastic electron tunneling spectroscopy. Threshold voltage for the reaction is approximately 365 mV, which coincides with the vibrational excitation of the C-H stretching mode. The reaction was ascertained to be caused by C-H bond dissociation by multiple vibrational excitations of the C-H stretching mode via inelastic electron tunneling process.
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Affiliation(s)
- Yousoo Kim
- RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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