151
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Electron transport properties of boron nitride fullerene B24N24 doped with lithium atom: first-principles calculations. Struct Chem 2013. [DOI: 10.1007/s11224-013-0299-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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152
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Wu Y, Hong W, Akiyama T, Gautsch S, Kolivoska V, Wandlowski T, de Rooij NF. Batch fabrication of gold-gold nanogaps by E-beam lithography and electrochemical deposition. NANOTECHNOLOGY 2013; 24:235302. [PMID: 23676659 DOI: 10.1088/0957-4484/24/23/235302] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We report on the successful development of a well-controlled two-step batch nano-fabrication process to achieve nanometer-size gaps at the wafer scale. The technique is based on an optimized electron-beam lithography process, which enables the fabrication of nanogaps in the range (15 ± 4) nm. Following this first step, the feedback-controlled electrochemical deposition of gold from an aqueous HAuCl4-based electrolyte is applied to further reduce the size of the gap down to about 0.3-1.0 nm. This protocol was successfully demonstrated by fabricating more than 385 nanogaps on a 4 inch wafer. The reproducible fabrication of nanogaps in the range between 0.3 and 1.0 nm opens up new perspectives for addressing the electrical and reactivity properties of single molecules and clusters in confined space under well-controlled conditions.
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Affiliation(s)
- Yexian Wu
- Sensors, Actuators and Microsystems Laboratory (SAMLAB), École Polytechnique Fédérale de Lausanne (EPFL), CH-2002, Neuchâtel, Switzerland.
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153
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Aradhya SV, Venkataraman L. Single-molecule junctions beyond electronic transport. NATURE NANOTECHNOLOGY 2013; 8:399-410. [PMID: 23736215 DOI: 10.1038/nnano.2013.91] [Citation(s) in RCA: 466] [Impact Index Per Article: 42.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 04/22/2013] [Indexed: 05/21/2023]
Abstract
The idea of using individual molecules as active electronic components provided the impetus to develop a variety of experimental platforms to probe their electronic transport properties. Among these, single-molecule junctions in a metal-molecule-metal motif have contributed significantly to our fundamental understanding of the principles required to realize molecular-scale electronic components from resistive wires to reversible switches. The success of these techniques and the growing interest of other disciplines in single-molecule-level characterization are prompting new approaches to investigate metal-molecule-metal junctions with multiple probes. Going beyond electronic transport characterization, these new studies are highlighting both the fundamental and applied aspects of mechanical, optical and thermoelectric properties at the atomic and molecular scales. Furthermore, experimental demonstrations of quantum interference and manipulation of electronic and nuclear spins in single-molecule circuits are heralding new device concepts with no classical analogues. In this Review, we present the emerging methods being used to interrogate multiple properties in single molecule-based devices, detail how these measurements have advanced our understanding of the structure-function relationships in molecular junctions, and discuss the potential for future research and applications.
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Affiliation(s)
- Sriharsha V Aradhya
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA
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154
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Affiliation(s)
- Emanuel Lörtscher
- IBM Research-Zurich Laboratory, Science & Technology Department, Säumerstrasse 4, CH-8803 Rüschlikon, Switzerland.
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155
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Wang LJ, Yong A, Zhou KG, Tan L, Ye J, Wu GP, Xu ZG, Zhang HL. Conformation-Controlled Electron Transport in Single-Molecule Junctions Containing Oligo(phenylene ethynylene) Derivatives. Chem Asian J 2013; 8:1901-9. [DOI: 10.1002/asia.201300264] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 04/07/2013] [Indexed: 11/11/2022]
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156
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Wang H, Thoss M. Numerically exact, time-dependent study of correlated electron transport in model molecular junctions. J Chem Phys 2013; 138:134704. [DOI: 10.1063/1.4798404] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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157
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Affiliation(s)
- Shaowei Chen
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064;
| | - Zhenhuan Zhao
- State Key Laboratory of Crystal Materials, Center of Bio and Micro/Nano Functional Materials, Shandong University, Jinan, Shandong 250100, China;
| | - Hong Liu
- State Key Laboratory of Crystal Materials, Center of Bio and Micro/Nano Functional Materials, Shandong University, Jinan, Shandong 250100, China;
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100085, China
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158
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Pobelov IV, Mohos M, Yoshida K, Kolivoska V, Avdic A, Lugstein A, Bertagnolli E, Leonhardt K, Denuault G, Gollas B, Wandlowski T. Electrochemical current-sensing atomic force microscopy in conductive solutions. NANOTECHNOLOGY 2013; 24:115501. [PMID: 23448801 DOI: 10.1088/0957-4484/24/11/115501] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Insulated atomic force microscopy probes carrying gold conductive tips were fabricated and employed as bifunctional force and current sensors in electrolyte solutions under electrochemical potential control. The application of the probes for current-sensing imaging, force and current-distance spectroscopy as well as scanning electrochemical microscopy experiments was demonstrated.
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Affiliation(s)
- Ilya V Pobelov
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland.
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159
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Nishino T, Hayashi N, Bui PT. Direct Measurement of Electron Transfer through a Hydrogen Bond between Single Molecules. J Am Chem Soc 2013; 135:4592-5. [DOI: 10.1021/ja311463b] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tomoaki Nishino
- Nanoscience and
Nanotechnology Research Center, Osaka Prefecture University, Sakai, Osaka 599-8570, Japan
| | - Nobuhiko Hayashi
- Nanoscience and
Nanotechnology Research Center, Osaka Prefecture University, Sakai, Osaka 599-8570, Japan
| | - Phuc T. Bui
- Department of Materials
Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
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160
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Electron Transfer at Gold Nanostar Assemblies: A Study of Shape Stability and Surface Density Influence. Catalysts 2013. [DOI: 10.3390/catal3010288] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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161
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Cao Y, Dong S, Liu S, Liu Z, Guo X. Toward Functional Molecular Devices Based on Graphene-Molecule Junctions. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201208210] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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162
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Cao Y, Dong S, Liu S, Liu Z, Guo X. Toward Functional Molecular Devices Based on Graphene-Molecule Junctions. Angew Chem Int Ed Engl 2013; 52:3906-10. [DOI: 10.1002/anie.201208210] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Indexed: 11/08/2022]
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163
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Conformation-dependent conductance through a molecular break junction. J Mol Model 2013; 19:4173-80. [PMID: 23440404 DOI: 10.1007/s00894-013-1794-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Accepted: 02/05/2013] [Indexed: 11/27/2022]
Abstract
Ab initio molecular dynamics simulations have been performed of a gold-1,4-benzenedithiol (BDT)-gold nanojunction under mechanical stress. For three different pulling rates between 10 and 40 m s(-1), it is found that the nanowire always ruptures between the second and third Au atom from the thiol sulfur. Larger rupture forces and longer extensions are required at higher pulling rates and vice versa. The electrical conductance was calculated along a pulling trajectory using the DFT-NEGF method to study the effect of thermal and stress-induced structural changes on the electrical transport properties. While the mechanically induced stretching of the junction is seen to lower the time-averaged conductance, thermal conformational changes are capable of altering the conductance by one order of magnitude. No single geometric quantity could be identified as the main contributor to the conductance fluctuations. Small modulations, however, can be explained in terms of C=C double bond vibrations in the BDT molecule. The dependence of the conductance on different geometric variables has further been investigated systematically by performing constrained geometry optimizations along a number of angle and dihedral coordinates. The largest changes in the conductance are observed when the Au-S-C angle and the Au-S-C-C dihedral are simultaneously constrained.
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164
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Chen IWP, Tseng WH, Gu MW, Su LC, Hsu CH, Chang WH, Chen CH. Tactile-feedback stabilized molecular junctions for the measurement of molecular conductance. Angew Chem Int Ed Engl 2013; 52:2449-53. [PMID: 23341350 DOI: 10.1002/anie.201207116] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 12/05/2012] [Indexed: 11/08/2022]
Abstract
Handling the (AFM) tip: The duration of stable molecular junctions was prolonged using a tactile feedback method in which the operator can sense the force of the AFM tip on the sample surface. The movement of the tip is adjusted accordingly, maintaining a more consistent current (i) and voltage (V), instead of having the tip move at a constant preset speed, as in the conventional setup.
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Affiliation(s)
- I-Wen Peter Chen
- Department of Applied Science, National Taitung University, Taitung, Taiwan 95002, Taiwan
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165
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Wen S, Yang G, Yan L, Li H, Su Z. Theoretical study on the rectifying performance of organoimido derivatives of hexamolybdates. Chemphyschem 2013; 14:610-7. [PMID: 23303530 DOI: 10.1002/cphc.201200770] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 11/29/2012] [Indexed: 11/11/2022]
Abstract
We design a new type of molecular diode, based on the organoimido derivatives of hexamolybdates, by exploring the rectifying performances using density functional theory combined with the non-equilibrium Green's function. Asymmetric current-voltage characteristics were obtained for the models with an unexpected large rectification ratio. The rectifying behavior can be understood by the asymmetrical shift of the transmission peak observed under different polarities. It is interesting to find that the preferred electron-transport direction in our studied system is different from that of the organic D-bridge-A system. The results show that the studied organic-inorganic hybrid systems have an intrinsically robust rectifying ratio, which should be taken into consideration in the design of the molecular diodes.
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Affiliation(s)
- Shizheng Wen
- Institute of Functional Material Chemistry, Faculty of Chemistry, Northeast Normal University, Changchun 130024, PR China
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166
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Ramos-Berdullas N, Mandado M. Electronic Properties ofp-Xylylene andp-Phenylene Chains Subjected to Finite Bias Voltages: A New Highly Conducting Oligophenyl Structure. Chemistry 2013; 19:3646-54. [DOI: 10.1002/chem.201203324] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 11/26/2012] [Indexed: 11/09/2022]
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167
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Chen IWP, Tseng WH, Gu MW, Su LC, Hsu CH, Chang WH, Chen CH. Tactile-Feedback Stabilized Molecular Junctions for the Measurement of Molecular Conductance. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201207116] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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168
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Sek S. Review peptides and proteins wired into the electrical circuits: An SPM-based approach. Biopolymers 2013; 100:71-81. [DOI: 10.1002/bip.22148] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Revised: 07/26/2012] [Accepted: 08/08/2012] [Indexed: 12/30/2022]
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169
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Kim CM, Bechhoefer J. Conductive probe AFM study of Pt-thiol and Au-thiol contacts in metal-molecule-metal systems. J Chem Phys 2013; 138:014707. [DOI: 10.1063/1.4773436] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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170
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Abstract
Single molecular junctions, in which a single molecule bridges between metal electrodes, have attracted wide attention as novel properties can appear due to their peculiar geometrical and electronic characters. The single molecular junction has also attracted attention due to its potential application in ultrasmall single molecular electronic devices, where single molecules are utilized as active electronic components. Thus, fabrication of single molecular junctions as well as understanding and controlling their properties (e.g. conductance, optical and magnetic properties) have become long-standing goals of scientists and engineers. This review article focuses on the experimental aspects of single molecular junctions, with primary focus on the electron transport mechanism.
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Affiliation(s)
- Manabu Kiguchi
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 W4-10 Ookayama, Tokyo 152-8551, Japan.
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171
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Della Pia EA, Chi Q, Macdonald JE, Ulstrup J, Jones DD, Elliott M. Fast electron transfer through a single molecule natively structured redox protein. NANOSCALE 2012; 4:7106-7113. [PMID: 23069929 DOI: 10.1039/c2nr32131a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The electron transfer properties of proteins are normally measured as molecularly averaged ensembles. Through these and related measurements, proteins are widely regarded as macroscopically insulating materials. Using scanning tunnelling microscopy (STM), we present new measurements of the conductance through single-molecules of the electron transfer protein cytochrome b(562) in its native conformation, under pseudo-physiological conditions. This is achieved by thiol (SH) linker pairs at opposite ends of the molecule through protein engineering, resulting in defined covalent contact between a gold surface and a platinum-iridium STM tip. Two different orientations of the linkers were examined: a long-axis configuration (SH-LA) and a short-axis configuration (SH-SA). In each case, the molecular conductance could be 'gated' through electrochemical control of the heme redox state. Reproducible and remarkably high conductance was observed in this relatively complex electron transfer system, with single-molecule conductance values peaking around 18 nS and 12 nS for the SH-SA and SH-LA cytochrome b(562) molecules near zero electrochemical overpotential. This strongly points to the important role of the heme co-factor bound to the natively structured protein. We suggest that the two-step model of protein electron transfer in the STM geometry requires a multi-electron transfer to explain such a high conductance. The model also yields a low value for the reorganisation energy, implying that solvent reorganisation is largely absent.
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172
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Pal PP, Dunietz BD. On the suppression and significance of ghost transmission in electron transport modeling of single molecule junctions. J Chem Phys 2012. [DOI: 10.1063/1.4767344] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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173
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Abstract
Several aspects of intermolecular effects in molecular conduction have been studied in recent years. These experimental and theoretical studies, made on several setups of molecular conduction junctions, have focused on the current-voltage characteristic that is usually dominated by the elastic transmission properties of such junctions. In this paper, we address cooperative intermolecular effects in the inelastic tunneling signal calculated for simple generic models of such systems. We find that peak heights in the inelastic (d(2)I/dE(2) vs E) spectrum may be affected by such cooperative effects even when direct intermolecular interactions can be disregarded. This finding suggests that comparing experimental results to calculations made on single-molecule junctions should be done with care.
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Affiliation(s)
- Michael Galperin
- Department of Chemistry & Biochemistry, University of California at San Diego, La Jolla, California 92093, USA
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174
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Wierzbinski E, Yin X, Werling K, Waldeck DH. The Effect of Oxygen Heteroatoms on the Single Molecule Conductance of Saturated Chains. J Phys Chem B 2012; 117:4431-41. [DOI: 10.1021/jp307902v] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Emil Wierzbinski
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Xing Yin
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Keith Werling
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - David H. Waldeck
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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175
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Elmalk AT, Salverda JM, Tabares LC, Canters GW, Aartsma TJ. Probing redox proteins on a gold surface by single molecule fluorescence spectroscopy. J Chem Phys 2012; 136:235101. [PMID: 22779620 DOI: 10.1063/1.4728107] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The interaction between the fluorescently labeled redox protein, azurin, and a thin gold film is characterized using single-molecule fluorescence intensity and lifetime measurements. Fluorescence quenching starts at distances below 2.3 nm from the gold surface. At shorter distances the quantum yield may decrease down to fourfold for direct attachment of the protein to bare gold. Outside of the quenching range, up to fivefold enhancement of the fluorescence is observed on average with increasing roughness of the gold layer. Fluorescence-detected redox activity of individual azurin molecules, with a lifetime switching ratio of 0.4, is demonstrated for the first time close to a gold surface.
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Affiliation(s)
- Abdalmohsen T Elmalk
- Leiden Institute of Physics, Leiden University, Huygens Laboratory, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
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176
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Cao Y, Dong S, Liu S, He L, Gan L, Yu X, Steigerwald ML, Wu X, Liu Z, Guo X. Building High-Throughput Molecular Junctions Using Indented Graphene Point Contacts. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201205607] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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177
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Cao Y, Dong S, Liu S, He L, Gan L, Yu X, Steigerwald ML, Wu X, Liu Z, Guo X. Building high-throughput molecular junctions using indented graphene point contacts. Angew Chem Int Ed Engl 2012; 51:12228-32. [PMID: 23125110 DOI: 10.1002/anie.201205607] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2012] [Revised: 08/28/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Yang Cao
- Center for NanoChemistry, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
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178
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Chang S, Sen S, Zhang P, Gyarfas B, Ashcroft B, Lefkowitz S, Peng H, Lindsay S. Palladium electrodes for molecular tunnel junctions. NANOTECHNOLOGY 2012; 23:425202. [PMID: 23037952 PMCID: PMC3501205 DOI: 10.1088/0957-4484/23/42/425202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Gold has been the metal of choice for research on molecular tunneling junctions, but it is incompatible with complementary metal-oxide-semiconductor fabrication because it forms deep level traps in silicon. Palladium electrodes do not contaminate silicon, and also give higher tunnel current signals in the molecular tunnel junctions that we have studied. The result is cleaner signals in a recognition-tunneling junction that recognizes the four natural DNA bases as well as 5-methyl cytosine, with no spurious background signals. More than 75% of all the recorded signal peaks indicate the base correctly.
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Affiliation(s)
- Shuai Chang
- Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
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179
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Wang YF, Néel N, Kröger J, Vázquez H, Brandbyge M, Wang B, Berndt R. Voltage-dependent conductance states of a single-molecule junction. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:394012. [PMID: 22964461 DOI: 10.1088/0953-8984/24/39/394012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Ag-Sn-phthalocyanine-Ag junctions are shown to exhibit three conductance states. While the junctions are conductive at low bias, their impedance drastically increases above a critical bias. Two-level fluctuations occur at intermediate bias. These characteristics may be used to protect a nanoscale circuit. Further experiments along with calculations reveal that the self-limiting conductance of the junctions is due to reversible changes of the junction geometry.
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Affiliation(s)
- Y F Wang
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, D-24098 Kiel, Germany.
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180
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Nef C, Frederix PLTM, Brunner J, Schönenberger C, Calame M. Force-conductance correlation in individual molecular junctions. NANOTECHNOLOGY 2012; 23:365201. [PMID: 22909952 DOI: 10.1088/0957-4484/23/36/365201] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Conducting atomic force microscopy is an attractive approach enabling the correlation of mechanical and electrical properties in individual molecular junctions. Here we report on measurements of gold-gold and gold-octanedithiol-gold junctions. We introduce two-dimensional histograms in the form of scatter plots to better analyze the correlation between force and conductance. In this representation, the junction-forming octanedithiol compounds lead to a very clear step in the force-conductance data, which is not observed for control monothiol compounds. The conductance found for octanedithiols is in agreement with the idea that junction conductance is dominated by a single molecule.
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Affiliation(s)
- C Nef
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
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181
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Della Pia EA, Macdonald JE, Elliott M, Jones DD. Direct binding of a redox protein for single-molecule electron transfer measurements. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:2341-2344. [PMID: 22549892 DOI: 10.1002/smll.201102416] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Revised: 02/16/2012] [Indexed: 05/31/2023]
Abstract
An electron transfer protein is engineered with two thiol groups introduced at different positions in the molecular structure to allow robust binding to two gold electrodes. Atomic force microscopy and scanning tunneling microscopy single-molecule studies show that the engineered proteins: (1) bind to a gold electrode in defined orientation dictated by the thiol-pair utilised, and (2) have a higher conductance than the wild-type proteins indicating a more efficient electron transmission due to the strong gold-thiol contacts.
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Affiliation(s)
- Eduardo A Della Pia
- School of Physics and Astronomy and School of Biosciences, Cardiff University, Cardiff, UK
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182
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Masillamani AM, Crivillers N, Orgiu E, Rotzler J, Bossert D, Thippeswamy R, Zharnikov M, Mayor M, Samorì P. Multiscale Charge Injection and Transport Properties in Self-Assembled Monolayers of Biphenyl Thiols with Varying Torsion Angles. Chemistry 2012; 18:10335-47. [DOI: 10.1002/chem.201201858] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Indexed: 11/06/2022]
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183
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Wen Y, Chen J, Guo Y, Wu B, Yu G, Liu Y. Multilayer graphene-coated atomic force microscopy tips for molecular junctions. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:3482-3485. [PMID: 22688906 DOI: 10.1002/adma.201200579] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 03/21/2012] [Indexed: 06/01/2023]
Abstract
Multilayer graphene tips are developed for conducting probe atomic force microscopy for the formation of molecular junctions. Molecular junctions using graphene tips show very small tip-to-tip variance, excellent operational stability, good endurance, and long shelf-life. These properties, together with high yield and the simple processing involved, suggest that commercial mass-production of graphene tips is viable for molecular electronic applications.
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Affiliation(s)
- Yugeng Wen
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190 Beijing, PR China
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184
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Synthesis and characterization of new hyperbranched poly(ether ketones) with various number of phenylene units. J IND ENG CHEM 2012. [DOI: 10.1016/j.jiec.2012.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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185
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Smaali K, Clément N, Patriarche G, Vuillaume D. Conductance statistics from a large array of sub-10 nm molecular junctions. ACS NANO 2012; 6:4639-47. [PMID: 22616578 DOI: 10.1021/nn301850g] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Devices made of few molecules constitute the miniaturization limit that both inorganic and organic-based electronics aspire to reach. However, integration of millions of molecular junctions with less than 100 molecules each has been a long technological challenge requiring well controlled nanometric electrodes. Here we report molecular junctions fabricated on a large array of sub-10 nm single crystal Au nanodots electrodes, a new approach that allows us to measure the conductance of up to a million of junctions in a single conducting atomic force microscope (C-AFM) image. We observe two peaks of conductance for alkylthiol molecules. Tunneling decay constant (β) for alkanethiols, is in the same range as previous studies. Energy position of molecular orbitals, obtained by transient voltage spectroscopy, varies from peak to peak, in correlation with conductance values.
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Affiliation(s)
- Kacem Smaali
- IEMN-CNRS , avenue Poincaré, Cité scientifique, Villeneuve d'Ascq, 59652, France.
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186
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Thuo MM, Reus WF, Simeone FC, Kim C, Schulz MD, Yoon HJ, Whitesides GM. Replacing −CH2CH2– with −CONH– Does Not Significantly Change Rates of Charge Transport through AgTS-SAM//Ga2O3/EGaIn Junctions. J Am Chem Soc 2012; 134:10876-84. [DOI: 10.1021/ja301778s] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Martin M. Thuo
- Department
of Chemistry and
Chemical Biology, Harvard University, 12
Oxford Street, Cambridge, Massachusetts 02138, United States
| | - William F. Reus
- Department
of Chemistry and
Chemical Biology, Harvard University, 12
Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Felice C. Simeone
- Department
of Chemistry and
Chemical Biology, Harvard University, 12
Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Choongik Kim
- Department
of Chemistry and
Chemical Biology, Harvard University, 12
Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Michael D. Schulz
- Department
of Chemistry and
Chemical Biology, Harvard University, 12
Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Hyo Jae Yoon
- Department
of Chemistry and
Chemical Biology, Harvard University, 12
Oxford Street, Cambridge, Massachusetts 02138, United States
| | - George M. Whitesides
- Department
of Chemistry and
Chemical Biology, Harvard University, 12
Oxford Street, Cambridge, Massachusetts 02138, United States
- Kavli Institute for Bionano Science & Technology, School of Engineering and Applied Sciences, Harvard University, Pierce Hall, 29 Oxford Street, Cambridge, Massachusetts 02138, United States
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187
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Tsutsui M, Taniguchi M. Single molecule electronics and devices. SENSORS (BASEL, SWITZERLAND) 2012; 12:7259-98. [PMID: 22969345 PMCID: PMC3435974 DOI: 10.3390/s120607259] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 05/15/2012] [Accepted: 05/17/2012] [Indexed: 11/21/2022]
Abstract
The manufacture of integrated circuits with single-molecule building blocks is a goal of molecular electronics. While research in the past has been limited to bulk experiments on self-assembled monolayers, advances in technology have now enabled us to fabricate single-molecule junctions. This has led to significant progress in understanding electron transport in molecular systems at the single-molecule level and the concomitant emergence of new device concepts. Here, we review recent developments in this field. We summarize the methods currently used to form metal-molecule-metal structures and some single-molecule techniques essential for characterizing molecular junctions such as inelastic electron tunnelling spectroscopy. We then highlight several important achievements, including demonstration of single-molecule diodes, transistors, and switches that make use of electrical, photo, and mechanical stimulation to control the electron transport. We also discuss intriguing issues to be addressed further in the future such as heat and thermoelectric transport in an individual molecule.
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Affiliation(s)
- Makusu Tsutsui
- The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan; E-Mail:
| | - Masateru Taniguchi
- The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan; E-Mail:
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188
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Pobelov IV, Mészáros G, Yoshida K, Mishchenko A, Gulcur M, Bryce MR, Wandlowski T. An approach to measure electromechanical properties of atomic and molecular junctions. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:164210. [PMID: 22466399 DOI: 10.1088/0953-8984/24/16/164210] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We describe a new setup for simultaneous measurements of force and current in conductive nanocontacts in a liquid environment with a high sampling rate and resolution. A lab-built current-to-voltage converter allows measurements of the current over seven orders of magnitude. As examples, we studied conductances and mechanical forces upon formation and breaking of gold atomic contacts and of two molecular junctions containing 1,2-di(4-pyridyl)ethyne (M1) and 1,4-di(4-pyridyl)buta-1,3-diyne (M2). We found that the forces required to deform or break gold atomic contacts depend critically on the surrounding medium. Further, they show non-linear behaviour in dependence of the number N of gold atoms detached. The electromechanical properties of the two types of molecular junctions upon stretching were analysed by correlating breaking forces with simultaneously measured junction conductances. A rather complex behaviour in a wide range of forces was discovered. Comparison of the current-probe atomic force microscopy experiments on the rupture of molecular junctions with STM-based break junction experiments enables the assignment of breaking forces of molecular junctions to the corresponding junction conductances.
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Affiliation(s)
- Ilya V Pobelov
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland.
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189
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Zhou J, Guo C, Xu B. Electron transport properties of single molecular junctions under mechanical modulations. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:164209. [PMID: 22466314 DOI: 10.1088/0953-8984/24/16/164209] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Electron transport behaviors of single molecular junctions are very sensitive to the atomic scale molecule-metal electrode contact interfaces, which have been difficult to control. We used a modified scanning probe microscope-break junction technique (SPM-BJT) to control the dynamics of the contacts and simultaneously monitor both the conductance and force. First, by fitting the measured data into a modified multiple tunneling barrier model, the static contact resistances, corresponding to the different contact conformations of single alkanedithiol and alkanediamine molecular junctions, were identified. Second, the changes of contact decay constant were measured under mechanical extensions of the molecular junctions, which helped to classify the different single molecular conductance sets into specific microscopic conformations of the molecule-electrode contacts. Third, by monitoring the changes of force and contact decay constant with the mechanical extensions, the changes of conductance were found to be caused by the changes of contact bond length and by the atomic reorganizations near the contact bond. This study provides a new insight into the understanding of the influences of contact conformations, especially the effect of changes of dynamic contact conformation on electron transport through single molecular junctions.
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Affiliation(s)
- Jianfeng Zhou
- Faculty of Engineering and Nanoscale Science and Engineering Center, University of Georgia, Athens, GA 30602, USA
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190
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Scullion LE, Leary E, Higgins SJ, Nichols RJ. Single-molecule conductance determinations on HS(CH2)4O(CH2)4SH and HS(CH2)2O(CH2)2O(CH2)2SH, and comparison with alkanedithiols of the same length. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:164211. [PMID: 22466424 DOI: 10.1088/0953-8984/24/16/164211] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The acetyl-protected, thiol-terminated ethers AcS(CH(2))(4)O(CH(2))(4)SAc and AcS(CH(2))(2)O(CH(2))(2)O(CH(2))(2)SAc have been synthesised, and a range of related scanning tunnelling microscopy (STM)-based methods have been employed to fabricate and electrically characterise gold | single molecule | gold junctions involving these molecules. The single-molecule conductance values obtained are consistently found to be substantially higher (by a factor of 2-3) than the conductances of analogous alkanedithiols of similar length (HS(CH(2))(9)SH and HS(CH(2))(8)SH, respectively). A rationalisation of these findings is suggested, namely that the lone pair electrons on the oxygen atoms are substantially closer in energy to the Fermi energy of the gold leads than are the occupied and unoccupied states of methylene chains, so that the ether oxygens behave in a manner analogous to 'wells' in a double-tunnelling-barrier system. In agreement with this suggestion, the current-voltage behaviour of the monoether can be fitted using the Simmons approach, and the barrier height is found to be significantly lower than for alkanedithiols of approximately the same length.
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Affiliation(s)
- Lisa E Scullion
- Department of Chemistry, University of Liverpool, Liverpool, UK
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191
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A density functional study on equilibrium geometries, stabilities and electronic properties of Au5Li binary clusters. APPLIED NANOSCIENCE 2012. [DOI: 10.1007/s13204-012-0092-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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192
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French WR, Iacovella CR, Cummings PT. Large-scale atomistic simulations of environmental effects on the formation and properties of molecular junctions. ACS NANO 2012; 6:2779-2789. [PMID: 22335340 DOI: 10.1021/nn300276m] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Using an updated simulation tool, we examine molecular junctions composed of benzene-1,4-dithiolate bonded between gold nanotips, focusing on the importance of environmental factors and interelectrode distance on the formation and structure of bridged molecules. We investigate the complex relationship between monolayer density and tip separation, finding that the formation of multimolecule junctions is favored at low monolayer density, while single-molecule junctions are favored at high density. We demonstrate that tip geometry and monolayer interactions, two factors that are often neglected in simulation, affect the bonding geometry and tilt angle of bridged molecules. We further show that the structures of bridged molecules at 298 and 77 K are similar.
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Affiliation(s)
- William R French
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37212, USA
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193
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194
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195
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Jelínek P, Ondráček M, Flores F. Relation between the chemical force and the tunnelling current in atomic point contacts: a simple model. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:084001. [PMID: 22311721 DOI: 10.1088/0953-8984/24/8/084001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The relation between the tunnelling current I(t) and the interaction energy/force E in an atomic-scale contact is discussed in the framework of a theoretical model established here. According to our model, we predict the existence of two characteristic scaling regimes, where the tunnelling current is either proportional to the interaction energy, I(t) ~ E, or to the square of the interaction energy, I(t) ~ E(2). We show that the existence of a given regime is basically controlled by two parameters: (i) the energy degeneracy Δ and (ii) the hopping t between electronic levels involved in the interaction process. In addition, we discuss the validity of the Bardeen method to determine the tunnelling current in the short tip-sample distances.
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Affiliation(s)
- Pavel Jelínek
- Institute of Physics, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
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196
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Dash LK, Ness H, Verstraete MJ, Godby RW. Functionality in single-molecule devices: Model calculations and applications of the inelastic electron tunneling signal in molecular junctions. J Chem Phys 2012; 136:064708. [DOI: 10.1063/1.3684627] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
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197
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Sedghi G, Esdaile LJ, Anderson HL, Martin S, Bethell D, Higgins SJ, Nichols RJ. Comparison of the conductance of three types of porphyrin-based molecular wires: β,meso,β-fused tapes, meso-Butadiyne-linked and twisted meso-meso linked oligomers. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:653-7. [PMID: 22083901 DOI: 10.1002/adma.201103109] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 10/15/2011] [Indexed: 05/04/2023]
Abstract
The length dependence of charge transport is evaluated in three families of porphyrin-based wires. Planar edge-fused tapes and alkyne-linked oligomers mediate efficient charge transport with exceptionally shallow distance dependence, whereas the conductances of the twisted singly linked chains decrease steeply with increasing oligomer length. The planar tapes are more conjugated than the alkyne-linked oligomers, but these two types of wires have similar conductance attenuation factors.
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Affiliation(s)
- Gita Sedghi
- Chemistry Department, University of Liverpool, Liverpool L69 7ZD, UK
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198
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Wierzbinski E, de Leon A, Davis KL, Bezer S, Wolak MA, Kofke MJ, Schlaf R, Achim C, Waldeck DH. Charge transfer through modified peptide nucleic acids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:1971-1981. [PMID: 22217076 DOI: 10.1021/la204445u] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We studied the charge transfer properties of bipyridine-modified peptide nucleic acid (PNA) in the absence and presence of Zn(II). Characterization of the PNA in solution showed that Zn(II) interacts with the bipyridine ligands, but the stability of the duplexes was not affected significantly by the binding of Zn(II). The charge transfer properties of these molecules were examined by electrochemistry for self-assembled monolayers of ferrocene-terminated PNAs and by conductive probe atomic force microscopy for cysteine-terminated PNAs. Both electrochemical and single molecular studies showed that the bipyridine modification and Zn(II) binding do not affect significantly the charge transfer of the PNA duplexes.
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Affiliation(s)
- Emil Wierzbinski
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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199
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Della Pia EA, Elliott M, Jones DD, Macdonald JE. Orientation-dependent electron transport in a single redox protein. ACS NANO 2012; 6:355-361. [PMID: 22088136 DOI: 10.1021/nn2036818] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The redox-active protein cytochrome b(562) has been engineered to introduce pairs of thiol groups in the form of cysteine residues at specified sites. Successful STM imaging of the molecules adsorbed on a gold surface indicated that one thiol group controls the orientation of the molecule and that the protein maintains its native form under the experimental conditions. Stable protein-gold STM tip electrical contact was directly observed to form via the second free thiol group in current-voltage and current-distance measurements. Proteins with thiol contacts positioned across the protein's short axis displayed a conductance of (3.48 ± 0.05) × 10(-5)G(0). However proteins with thiol groups placed along the long axis reproducibly yielded two distinct values of (1.95 ± 0.03) × 10(-5)G(0) and (3.57 ± 0.11) × 10(-5)G(0), suggesting that the placement of the asymmetrically located haem within the protein influences electron transfer. In contrast, the unengineered wild-type cytochrome b(562) had conductance values at least 1 order of magnitude less. Here we show that an electron transfer protein engineered to bind gold surfaces can be controllably oriented and electrically contacted to metallic electrodes, a prerequisite for potential integration into electronic circuits.
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200
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Hong W, Manrique DZ, Moreno-García P, Gulcur M, Mishchenko A, Lambert CJ, Bryce MR, Wandlowski T. Single Molecular Conductance of Tolanes: Experimental and Theoretical Study on the Junction Evolution Dependent on the Anchoring Group. J Am Chem Soc 2012; 134:2292-304. [PMID: 22175273 DOI: 10.1021/ja209844r] [Citation(s) in RCA: 274] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Wenjing Hong
- Department of Chemistry and
Biochemistry, University of Bern, Freiestrasse
3, CH-3012 Bern, Switzerland
| | | | - Pavel Moreno-García
- Department of Chemistry and
Biochemistry, University of Bern, Freiestrasse
3, CH-3012 Bern, Switzerland
- Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apartado Postal J-48, Puebla
72570, México
| | - Murat Gulcur
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Artem Mishchenko
- Department of Chemistry and
Biochemistry, University of Bern, Freiestrasse
3, CH-3012 Bern, Switzerland
| | - Colin J. Lambert
- Department of Physics, Lancaster University, Lancaster LA1 4YB, England
| | - Martin R. Bryce
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Thomas Wandlowski
- Department of Chemistry and
Biochemistry, University of Bern, Freiestrasse
3, CH-3012 Bern, Switzerland
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