1
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O'Driscoll LJ, Jay M, Robinson BJ, Sadeghi H, Wang X, Penhale-Jones B, Bryce MR, Lambert CJ. Planar aromatic anchors control the electrical conductance of gold|molecule|graphene junctions. NANOSCALE ADVANCES 2023; 5:2299-2306. [PMID: 37056609 PMCID: PMC10089101 DOI: 10.1039/d2na00873d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 03/08/2023] [Indexed: 06/19/2023]
Abstract
The synthesis of a family of alkanethiol molecules with planar aromatic head groups, designed to anchor molecules effectively to graphene electrodes, is reported. Characterisation of self-assembled monolayers of these molecules on a gold surface via conductive atomic force microscopy shows that when an aromatic head group is present, the conductance G graphene obtained using a graphene coated probe is higher than the conductance G Pt obtained using a platinum (Pt) probe. For Pt probe and graphene probe junctions, the tunnelling decay constant of benzyl ether derivatives with an alkanethiol molecular backbone is determined as β = 5.6 nm-1 and 3.5 nm-1, respectively. The conductance ratio G graphene/G Pt increases as the number of rings present in the aromatic head unit, n, increases. However, as the number of rings increases, the conductance path length increases because the planar head groups lie at an angle to the plane of the electrodes. This means that overall conductance decreases as n increases. Density functional theory-based charge transport calculations support these experimental findings. This study confirms that planar aromatic head groups can function as effective anchoring units for graphene electrodes in large area molecular junctions. However, the results also indicate that the size and geometry of these head groups must be considered in order to produce effective molecular designs.
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Affiliation(s)
| | - Michael Jay
- Dept. of Physics, Lancaster University Lancaster LA1 4YB UK
| | | | - Hatef Sadeghi
- Dept. of Engineering, Warwick University Coventry CV4 7AL UK
| | - Xintai Wang
- School of Information Science and Technology, Dalian Maritime University Dalian China
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2
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Deffner M, Weise MP, Zhang H, Mücke M, Proppe J, Franco I, Herrmann C. Learning Conductance: Gaussian Process Regression for Molecular Electronics. J Chem Theory Comput 2023; 19:992-1002. [PMID: 36692968 DOI: 10.1021/acs.jctc.2c00648] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Experimental studies of charge transport through single molecules often rely on break junction setups, where molecular junctions are repeatedly formed and broken while measuring the conductance, leading to a statistical distribution of conductance values. Modeling this experimental situation and the resulting conductance histograms is challenging for theoretical methods, as computations need to capture structural changes in experiments, including the statistics of junction formation and rupture. This type of extensive structural sampling implies that even when evaluating conductance from computationally efficient electronic structure methods, which typically are of reduced accuracy, the evaluation of conductance histograms is too expensive to be a routine task. Highly accurate quantum transport computations are only computationally feasible for a few selected conformations and thus necessarily ignore the rich conformational space probed in experiments. To overcome these limitations, we investigate the potential of machine learning for modeling conductance histograms, in particular by Gaussian process regression. We show that by selecting specific structural parameters as features, Gaussian process regression can be used to efficiently predict the zero-bias conductance from molecular structures, reducing the computational cost of simulating conductance histograms by an order of magnitude. This enables the efficient calculation of conductance histograms even on the basis of computationally expensive first-principles approaches by effectively reducing the number of necessary charge transport calculations, paving the way toward their routine evaluation.
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Affiliation(s)
- Michael Deffner
- Institute of Inorganic and Applied Chemistry, University of Hamburg, Hamburg22761, Germany.,The Hamburg Centre for Ultrafast Imaging, Hamburg22761, Germany
| | - Marc Philipp Weise
- Institute of Inorganic and Applied Chemistry, University of Hamburg, Hamburg22761, Germany
| | - Haitao Zhang
- Institute of Inorganic and Applied Chemistry, University of Hamburg, Hamburg22761, Germany
| | - Maike Mücke
- Institute of Physical Chemistry, Georg-August University, Göttingen37077, Germany
| | - Jonny Proppe
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Braunschweig38106, Germany
| | - Ignacio Franco
- Departments of Chemistry and Physics, University of Rochester, Rochester, New York14627-0216, United States
| | - Carmen Herrmann
- Institute of Inorganic and Applied Chemistry, University of Hamburg, Hamburg22761, Germany.,The Hamburg Centre for Ultrafast Imaging, Hamburg22761, Germany
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3
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Kocábová J, Vavrek F, Nováková Lachmanová Š, Šebera J, Valášek M, Hromadová M. Self-Assembled Monolayers of Molecular Conductors with Terpyridine-Metal Redox Switching Elements: A Combined AFM, STM and Electrochemical Study. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238320. [PMID: 36500413 PMCID: PMC9738775 DOI: 10.3390/molecules27238320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/23/2022] [Accepted: 11/24/2022] [Indexed: 12/02/2022]
Abstract
Self-assembled monolayers (SAMs) of terpyridine-based transition metal (ruthenium and osmium) complexes, anchored to gold substrate via tripodal anchoring groups, have been investigated as possible redox switching elements for molecular electronics. An electrochemical study was complemented by atomic force microscopy (AFM) and scanning tunneling microscopy (STM) methods. STM was used for determination of the SAM conductance values, and computation of the attenuation factor β from tunneling current-distance curves. We have shown that SAMs of Os-tripod molecules contain larger adlayer structures compared with SAMs of Ru-tripod molecules, which are characterized by a large number of almost evenly distributed small islands. Furthermore, upon cyclic voltammetric experimentation, Os-tripod films rearrange to form a smaller number of even larger islands, reminiscent of the Ostwald ripening process. Os-tripod SAMs displayed a higher surface concentration of molecules and lower conductance compared with Ru-tripod SAMs. The attenuation factor of Os-tripod films changed dramatically, upon electrochemical cycling, to a higher value. These observations are in accordance with previously reported electron transfer kinetics studies.
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Affiliation(s)
- Jana Kocábová
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic
| | - František Vavrek
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic
| | - Štěpánka Nováková Lachmanová
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic
| | - Jakub Šebera
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic
| | - Michal Valášek
- Institute of Nanotechnology, Karlsruhe Institute of Technology, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Magdaléna Hromadová
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic
- Correspondence:
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4
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Yamada Y, Iida H, Shibano S, Mihara N, Kato T, Tanaka K. Significant Effect of the Flexibility of Bridging Alkyl Chains on the Proximity of Stacked Porphyrin and Phthalocyanine Conjugated with a Fourfold Rotaxane Linkage. Chemistry 2022; 28:e202200819. [DOI: 10.1002/chem.202200819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Indexed: 11/05/2022]
Affiliation(s)
- Yasuyuki Yamada
- Department of Chemistry Graduate School of Science Nagoya University Furo-cho, Chikusa-ku Nagoya 464-8602 Japan
- Research Center for Materials Science Nagoya University Furo-cho, Chikusa-ku Nagoya 464-8602 Japan
| | - Hayato Iida
- Department of Chemistry Graduate School of Science Nagoya University Furo-cho, Chikusa-ku Nagoya 464-8602 Japan
| | - Shinya Shibano
- Department of Chemistry Graduate School of Science Nagoya University Furo-cho, Chikusa-ku Nagoya 464-8602 Japan
| | - Nozomi Mihara
- Department of Chemistry Graduate School of Science Nagoya University Furo-cho, Chikusa-ku Nagoya 464-8602 Japan
| | - Tatsuhisa Kato
- Fukui Institute for Fundamental Chemistry Kyoto University Takano-Nishihiraki-cho, Sakyo-ku Kyoto 606-8103 Japan
| | - Kentaro Tanaka
- Department of Chemistry Graduate School of Science Nagoya University Furo-cho, Chikusa-ku Nagoya 464-8602 Japan
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5
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Poluektov G, Keller TJ, Jochemich A, Krönert A, Müller U, Spicher S, Grimme S, Jester S, Höger S. Supramolecular Nanopatterns of Molecular Spoked Wheels with Orthogonal Pillars: The Observation of a Fullerene Haze. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Georgiy Poluektov
- Kekulé-Institut für Organische Chemie und Biochemie Rheinische Friedrich-Wilhelms-Universität Bonn Gerhard-Domagk-Str. 1 53121 Bonn Germany
| | - Tristan J. Keller
- Kekulé-Institut für Organische Chemie und Biochemie Rheinische Friedrich-Wilhelms-Universität Bonn Gerhard-Domagk-Str. 1 53121 Bonn Germany
| | - Anna Jochemich
- Kekulé-Institut für Organische Chemie und Biochemie Rheinische Friedrich-Wilhelms-Universität Bonn Gerhard-Domagk-Str. 1 53121 Bonn Germany
| | - Anna Krönert
- Kekulé-Institut für Organische Chemie und Biochemie Rheinische Friedrich-Wilhelms-Universität Bonn Gerhard-Domagk-Str. 1 53121 Bonn Germany
| | - Ute Müller
- Kekulé-Institut für Organische Chemie und Biochemie Rheinische Friedrich-Wilhelms-Universität Bonn Gerhard-Domagk-Str. 1 53121 Bonn Germany
| | - Sebastian Spicher
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich-Wilhelms-Universität Bonn Beringstr. 4 53115 Bonn Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich-Wilhelms-Universität Bonn Beringstr. 4 53115 Bonn Germany
| | - Stefan‐S. Jester
- Kekulé-Institut für Organische Chemie und Biochemie Rheinische Friedrich-Wilhelms-Universität Bonn Gerhard-Domagk-Str. 1 53121 Bonn Germany
| | - Sigurd Höger
- Kekulé-Institut für Organische Chemie und Biochemie Rheinische Friedrich-Wilhelms-Universität Bonn Gerhard-Domagk-Str. 1 53121 Bonn Germany
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6
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Poluektov G, Keller TJ, Jochemich A, Krönert A, Müller U, Spicher S, Grimme S, Jester SS, Höger S. Supramolecular Nanopatterns of Molecular Spoked Wheels with Orthogonal Pillars: The Observation of a Fullerene Haze. Angew Chem Int Ed Engl 2021; 60:27264-27270. [PMID: 34672411 PMCID: PMC9298702 DOI: 10.1002/anie.202111869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Indexed: 11/08/2022]
Abstract
Molecular spoked wheels with intraannular functionalizable pillars are synthesized in a modular approach. The functionalities at their ends are variable, and a propargyl alcohol, a [6,6]-phenyl-C61-butyrate, and a perylene monoimide are investigated. All compounds form two-dimensional crystals on highly oriented pyrolytic graphite at the solid-liquid interface. As determined by submolecularly resolved scanning tunneling microscopy, the pillars adopt equilibrium distances of 6.0 nm. The fullerene has a residual mobility, limited by the length of the flexible connector unit. The experimental results are supported and rationalized by molecular dynamics simulations. These also show that, in contrast, the more rigidly attached perylene monoimide units remain oriented along the surface normal and maintain a smallest distance of 2 nm above the graphite substrate. The robust packing concept also holds for cocrystals with molecular hexagons that expand the pillar-pillar distances by 15 % and block unspecific intercalation.
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Affiliation(s)
- Georgiy Poluektov
- Kekulé-Institut für Organische Chemie und Biochemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Tristan J Keller
- Kekulé-Institut für Organische Chemie und Biochemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Anna Jochemich
- Kekulé-Institut für Organische Chemie und Biochemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Anna Krönert
- Kekulé-Institut für Organische Chemie und Biochemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Ute Müller
- Kekulé-Institut für Organische Chemie und Biochemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Sebastian Spicher
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4, 53115, Bonn, Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4, 53115, Bonn, Germany
| | - Stefan-S Jester
- Kekulé-Institut für Organische Chemie und Biochemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Sigurd Höger
- Kekulé-Institut für Organische Chemie und Biochemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
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7
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Balzer N, Lukášek J, Valášek M, Rai V, Sun Q, Gerhard L, Wulfhekel W, Mayor M. Synthesis and Surface Behaviour of NDI Chromophores Mounted on a Tripodal Scaffold: Towards Self-Decoupled Chromophores for Single-Molecule Electroluminescence. Chemistry 2021; 27:12144-12155. [PMID: 34152041 PMCID: PMC8457086 DOI: 10.1002/chem.202101264] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Indexed: 12/01/2022]
Abstract
This paper reports the efficient synthesis, absorption and emission spectra, and the electrochemical properties of a series of 2,6-disubstituted naphthalene-1,4,5,8-tetracarboxdiimide (NDI) tripodal molecules with thioacetate anchors for their surface investigations. Our studies showed that, in particular, the pyrrolidinyl group with its strong electron-donating properties enhanced the fluorescence of such core-substituted NDI chromophores and caused a significant bathochromic shift in the absorption spectrum with a correspondingly narrowed bandgap of 1.94 eV. Cyclic voltammetry showed the redox properties of NDIs to be influenced by core substituents. The strong electron-donating character of pyrrolidine substituents results in rather high HOMO and LUMO levels of -5.31 and -3.37 eV when compared with the parental unsubstituted NDI. UHV-STM measurements of a sub-monolayer of the rigid tripodal NDI chromophores spray deposited on Au(111) show that these molecules mainly tend to adsorb flat in a pairwise fashion on the surface and form unordered films. However, the STML experiments also revealed a few molecular clusters, which might consist of upright oriented molecules protruding from the molecular island and show electroluminescence photon spectra with high electroluminescence yields of up to 6×10-3 . These results demonstrate the promising potential of the NDI tripodal chromophores for the fabrication of molecular devices profiting from optical features of the molecular layer.
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Affiliation(s)
- Nico Balzer
- Institute of NanotechnologyKarlsruhe Institute of TechnologyP.O. Box 364076021KarlsruheGermany
| | - Jan Lukášek
- Institute of NanotechnologyKarlsruhe Institute of TechnologyP.O. Box 364076021KarlsruheGermany
| | - Michal Valášek
- Institute of NanotechnologyKarlsruhe Institute of TechnologyP.O. Box 364076021KarlsruheGermany
| | - Vibhuti Rai
- Institute of Quantum Materials and TechnologiesKarlsruhe Institute of Technology76021KarlsruheGermany
| | - Qing Sun
- Institute of Quantum Materials and TechnologiesKarlsruhe Institute of Technology76021KarlsruheGermany
| | - Lukas Gerhard
- Institute of Quantum Materials and TechnologiesKarlsruhe Institute of Technology76021KarlsruheGermany
| | - Wulf Wulfhekel
- Institute of Quantum Materials and TechnologiesKarlsruhe Institute of Technology76021KarlsruheGermany
- Physikalisches InstitutKarlsruhe Institute of TechnologyWolfgang-Gaede-Straße 176131KarlsruheGermany
| | - Marcel Mayor
- Institute of NanotechnologyKarlsruhe Institute of TechnologyP.O. Box 364076021KarlsruheGermany
- Department of ChemistryUniversity of BaselSt. Johanns-Ring 194056BaselSwitzerland
- Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou, Guangdong510275P. R. China
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8
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Das S, Nascimbeni G, de la Morena RO, Ishiwari F, Shoji Y, Fukushima T, Buck M, Zojer E, Zharnikov M. Porous Honeycomb Self-Assembled Monolayers: Tripodal Adsorption and Hidden Chirality of Carboxylate Anchored Triptycenes on Ag. ACS NANO 2021; 15:11168-11179. [PMID: 34125529 PMCID: PMC8320238 DOI: 10.1021/acsnano.1c03626] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/08/2021] [Indexed: 06/12/2023]
Abstract
Molecules with tripodal anchoring to substrates represent a versatile platform for the fabrication of robust self-assembled monolayers (SAMs), complementing the conventional monopodal approach. In this context, we studied the adsorption of 1,8,13-tricarboxytriptycene (Trip-CA) on Ag(111), mimicked by a bilayer of silver atoms underpotentially deposited on Au. While tripodal SAMs frequently suffer from poor structural quality and inhomogeneous bonding configurations, the triptycene scaffold featuring three carboxylic acid anchoring groups yields highly crystalline SAM structures. A pronounced polymorphism is observed, with the formation of distinctly different structures depending on preparation conditions. Besides hexagonal molecular arrangements, the occurrence of a honeycomb structure is particularly intriguing as such an open structure is unusual for SAMs consisting of upright-standing molecules. Advanced spectroscopic tools reveal an equivalent bonding of all carboxylic acid anchoring groups. Notably, density functional theory calculations predict a chiral arrangement of the molecules in the honeycomb network, which, surprisingly, is not apparent in experimental scanning tunneling microscopy (STM) images. This seeming discrepancy between theory and experiment can be resolved by considering the details of the actual electronic structure of the adsorbate layer. The presented results represent an exemplary showcase for the intricacy of interpreting STM images of complex molecular films. They are also further evidence for the potential of triptycenes as basic building blocks for generating well-defined layers with unusual structural motifs.
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Affiliation(s)
- Saunak Das
- Angewandte
Physikalische Chemie, Universität
Heidelberg, Im Neuenheimer Feld 253, D-69120 Heidelberg, Germany
| | - Giulia Nascimbeni
- Institute
of Solid State Physics, NAWI Graz, Graz
University of Technology, Petersgasse 16, 8010 Graz, Austria
| | | | - Fumitaka Ishiwari
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta,
Midori-ku, Yokohama 226-8503, Japan
| | - Yoshiaki Shoji
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta,
Midori-ku, Yokohama 226-8503, Japan
| | - Takanori Fukushima
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta,
Midori-ku, Yokohama 226-8503, Japan
| | - Manfred Buck
- EaStCHEM
School of Chemistry, University of St Andrews, North Haugh, St Andrews KY16 9ST, U.K.
| | - Egbert Zojer
- Institute
of Solid State Physics, NAWI Graz, Graz
University of Technology, Petersgasse 16, 8010 Graz, Austria
| | - Michael Zharnikov
- Angewandte
Physikalische Chemie, Universität
Heidelberg, Im Neuenheimer Feld 253, D-69120 Heidelberg, Germany
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9
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Metzelaars M, Schleicher S, Hattori T, Borca B, Matthes F, Sanz S, Bürgler DE, Rawson J, Schneider CM, Kögerler P. Cyclophane with eclipsed pyrene units enables construction of spin interfaces with chemical accuracy. Chem Sci 2021; 12:8430-8437. [PMID: 34221324 PMCID: PMC8221062 DOI: 10.1039/d1sc01036k] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Advanced functionality in molecular electronics and spintronics is orchestrated by exact molecular arrangements at metal surfaces, but the strategies for constructing such arrangements remain limited. Here, we report the synthesis and surface hybridization of a cyclophane that comprises two pyrene groups fastened together by two ferrocene pillars. Crystallographic structure analysis revealed pyrene planes separated by ∼352 pm and stacked in an eclipsed geometry that approximates the rare configuration of AA-stacked bilayer graphene. We deposited this cyclophane onto surfaces of Cu(111) and Co(111) at submonolayer coverage and studied the resulting hybrid entities with scanning tunnelling microscopy (STM). We found distinct characteristics of this cyclophane on each metal surface: on non-magnetic Cu(111), physisorption occurred and the two pyrene groups remained electronically coupled to each other; on ferromagnetic Co(111) nanoislands, chemisorption occurred and the two pyrene groups became electronically decoupled. Spin-polarized STM measurements revealed that the ferrocene groups had spin polarization opposite to that of the surrounding Co metal, while the pyrene stack had no spin polarization. Comparisons to the non-stacked analogue comprising only one pyrene group bolster our interpretation of the cyclophane's STM features. The design strategy presented herein can be extended to realize versatile, three-dimensional platforms in single-molecule electronics and spintronics. A chemical strategy for the bottom-up construction of 3D spin interfaces is presented. Scanning tunnelling microscopy reveals distinct electronic features of a cyclophane with precisely designed pi-stacking on ferromagnetic Co(111) nanoislands.![]()
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Affiliation(s)
- Marvin Metzelaars
- Institute of Inorganic Chemistry, RWTH Aachen University 52074 Aachen Germany
| | | | - Takuma Hattori
- Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich 52428 Jülich Germany
| | - Bogdana Borca
- Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich 52428 Jülich Germany .,National Institute of Materials Physics Atomistilor 405A, Magurele 077125 Ilfov Romania
| | - Frank Matthes
- Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich 52428 Jülich Germany
| | - Sergio Sanz
- Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich 52428 Jülich Germany
| | - Daniel E Bürgler
- Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich 52428 Jülich Germany
| | - Jeff Rawson
- Institute of Inorganic Chemistry, RWTH Aachen University 52074 Aachen Germany.,Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich 52428 Jülich Germany
| | - Claus M Schneider
- Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich 52428 Jülich Germany
| | - Paul Kögerler
- Institute of Inorganic Chemistry, RWTH Aachen University 52074 Aachen Germany.,Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich 52428 Jülich Germany
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10
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Nanofabrication Techniques in Large-Area Molecular Electronic Devices. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10176064] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The societal impact of the electronics industry is enormous—not to mention how this industry impinges on the global economy. The foreseen limits of the current technology—technical, economic, and sustainability issues—open the door to the search for successor technologies. In this context, molecular electronics has emerged as a promising candidate that, at least in the short-term, will not likely replace our silicon-based electronics, but improve its performance through a nascent hybrid technology. Such technology will take advantage of both the small dimensions of the molecules and new functionalities resulting from the quantum effects that govern the properties at the molecular scale. An optimization of interface engineering and integration of molecules to form densely integrated individually addressable arrays of molecules are two crucial aspects in the molecular electronics field. These challenges should be met to establish the bridge between organic functional materials and hard electronics required for the incorporation of such hybrid technology in the market. In this review, the most advanced methods for fabricating large-area molecular electronic devices are presented, highlighting their advantages and limitations. Special emphasis is focused on bottom-up methodologies for the fabrication of well-ordered and tightly-packed monolayers onto the bottom electrode, followed by a description of the top-contact deposition methods so far used.
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11
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Jasper-Toennies T, Gruber M, Johannsen S, Frederiksen T, Garcia-Lekue A, Jäkel T, Roehricht F, Herges R, Berndt R. Rotation of Ethoxy and Ethyl Moieties on a Molecular Platform on Au(111). ACS NANO 2020; 14:3907-3916. [PMID: 32073820 DOI: 10.1021/acsnano.0c00029] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Molecular rotors have attracted considerable interest for their prospects in nanotechnology. However, their adsorption on supporting substrates, where they may be addressed individually, usually modifies their properties. Here, we investigate the switching of two closely related three-state rotors mounted on platforms on Au(111) using low-temperature scanning tunneling microscopy and density functional theory calculations. Being physisorbed, the platforms retain important gas-phase properties of the rotor. This simplifies a detailed analysis and permits, for instance, the identification of the vibrational modes involved in the rotation process. The symmetry provided by the platform enables active control of the rotation direction through electrostatic interactions with the tip and charged neighboring adsorbates. The present investigation of two model systems may turn out useful for designing platforms that provide directional rotation and for transferring more sophisticated molecular machines from the gas phase to surfaces.
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Affiliation(s)
- Torben Jasper-Toennies
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Manuel Gruber
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Sven Johannsen
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Thomas Frederiksen
- Donostia International Physics Center, DIPC, Paseo Manuel de Lardizabal 4, E-20018 Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao, Spain
| | - Aran Garcia-Lekue
- Donostia International Physics Center, DIPC, Paseo Manuel de Lardizabal 4, E-20018 Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao, Spain
| | - Torben Jäkel
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Fynn Roehricht
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Rainer Herges
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098 Kiel, Germany
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12
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Jasper-Tönnies T, Gruber M, Ulrich S, Herges R, Berndt R. Coverage-Controlled Superstructures of C 3 -Symmetric Molecules: Honeycomb versus Hexagonal Tiling. Angew Chem Int Ed Engl 2020; 59:7008-7017. [PMID: 32106353 PMCID: PMC7216838 DOI: 10.1002/anie.202001383] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Indexed: 11/06/2022]
Abstract
The competition between honeycomb and hexagonal tiling of molecular units can lead to large honeycomb superstructures on surfaces. Such superstructures exhibit pores that may be used as 2D templates for functional guest molecules. Honeycomb superstructures of molecules that comprise a C3 symmetric platform on Au(111) and Ag(111) surfaces are presented. The superstructures cover nearly mesoscopic areas with unit cells containing up to 3000 molecules, more than an order of magnitude larger than previously reported. The unit cell size may be controlled by the coverage. A fairly general model was developed to describe the energetics of honeycomb superstructures built from C3 symmetric units. Based on three parameters that characterize two competing bonding arrangements, the model is consistent with the present experimental data and also reproduces various published results. The model identifies the relevant driving force, mostly related to geometric aspects, of the pattern formation.
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Affiliation(s)
- Torben Jasper-Tönnies
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098, Kiel, Germany
| | - Manuel Gruber
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098, Kiel, Germany
| | - Sandra Ulrich
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität, 24098, Kiel, Germany
| | - Rainer Herges
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität, 24098, Kiel, Germany
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098, Kiel, Germany
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13
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Jasper‐Tönnies T, Gruber M, Ulrich S, Herges R, Berndt R. Coverage‐Controlled Superstructures of
C
3
‐Symmetric Molecules: Honeycomb versus Hexagonal Tiling. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202001383] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Torben Jasper‐Tönnies
- Institut für Experimentelle und Angewandte Physik Christian-Albrechts-Universität 24098 Kiel Germany
| | - Manuel Gruber
- Institut für Experimentelle und Angewandte Physik Christian-Albrechts-Universität 24098 Kiel Germany
| | - Sandra Ulrich
- Otto-Diels-Institut für Organische Chemie Christian-Albrechts-Universität 24098 Kiel Germany
| | - Rainer Herges
- Otto-Diels-Institut für Organische Chemie Christian-Albrechts-Universität 24098 Kiel Germany
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik Christian-Albrechts-Universität 24098 Kiel Germany
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14
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O'Driscoll LJ, Wang X, Jay M, Batsanov AS, Sadeghi H, Lambert CJ, Robinson BJ, Bryce MR. Carbazole-Based Tetrapodal Anchor Groups for Gold Surfaces: Synthesis and Conductance Properties. Angew Chem Int Ed Engl 2020; 59:882-889. [PMID: 31714641 PMCID: PMC7027450 DOI: 10.1002/anie.201911652] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Indexed: 12/17/2022]
Abstract
As the field of molecular-scale electronics matures and the prospect of devices incorporating molecular wires becomes more feasible, it is necessary to progress from the simple anchor groups used in fundamental conductance studies to more elaborate anchors designed with device stability in mind. This study presents a series of oligo(phenylene-ethynylene) wires with one tetrapodal anchor and a phenyl or pyridyl head group. The new anchors are designed to bind strongly to gold surfaces without disrupting the conductance pathway of the wires. Conductive probe atomic force microscopy (cAFM) was used to determine the conductance of self-assembled monolayers (SAMs) of the wires in Au-SAM-Pt and Au-SAM-graphene junctions, from which the conductance per molecule was derived. For tolane-type wires, mean conductances per molecule of up to 10-4.37 G0 (Pt) and 10-3.78 G0 (graphene) were measured, despite limited electronic coupling to the Au electrode, demonstrating the potential of this approach. Computational studies of the surface binding geometry and transport properties rationalise and support the experimental results.
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Affiliation(s)
- Luke J. O'Driscoll
- Department of ChemistryDurham University, Lower MountjoyStockton RoadDurhamDH1 3LEUK
| | - Xintai Wang
- Physics DepartmentLancaster UniversityLancasterLA1 4YBUK
| | - Michael Jay
- Physics DepartmentLancaster UniversityLancasterLA1 4YBUK
| | - Andrei S. Batsanov
- Department of ChemistryDurham University, Lower MountjoyStockton RoadDurhamDH1 3LEUK
| | - Hatef Sadeghi
- Physics DepartmentLancaster UniversityLancasterLA1 4YBUK
- School of EngineeringUniversity of WarwickCoventryCV4 7ALUK
| | | | | | - Martin R. Bryce
- Department of ChemistryDurham University, Lower MountjoyStockton RoadDurhamDH1 3LEUK
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15
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O'Driscoll LJ, Wang X, Jay M, Batsanov AS, Sadeghi H, Lambert CJ, Robinson BJ, Bryce MR. Carbazole‐Based Tetrapodal Anchor Groups for Gold Surfaces: Synthesis and Conductance Properties. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201911652] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Luke J. O'Driscoll
- Department of ChemistryDurham University, Lower Mountjoy Stockton Road Durham DH1 3LE UK
| | - Xintai Wang
- Physics DepartmentLancaster University Lancaster LA1 4YB UK
| | - Michael Jay
- Physics DepartmentLancaster University Lancaster LA1 4YB UK
| | - Andrei S. Batsanov
- Department of ChemistryDurham University, Lower Mountjoy Stockton Road Durham DH1 3LE UK
| | - Hatef Sadeghi
- Physics DepartmentLancaster University Lancaster LA1 4YB UK
- School of EngineeringUniversity of Warwick Coventry CV4 7AL UK
| | | | | | - Martin R. Bryce
- Department of ChemistryDurham University, Lower Mountjoy Stockton Road Durham DH1 3LE UK
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16
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Delarue Bizzini L, Zwick P, Mayor M. Preparation of Unsymmetrical Disulfides from Thioacetates and Thiosulfonates. European J Org Chem 2019. [DOI: 10.1002/ejoc.201901283] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | - Patrick Zwick
- Department of Chemistry; University of Basel; St. Johanns-Ring 19 4056 Basel Switzerland
| | - Marcel Mayor
- Department of Chemistry; University of Basel; St. Johanns-Ring 19 4056 Basel Switzerland
- Institute for Nanotechnology (INT); Karlsruhe Institute of Technology (KIT); P. O. Box 3640 76021 Karlsruhe Germany
- Lehn Institute of Functional Materials (LIFM); School of Chemistry; Sun Yat-Sen University; 510275 Guangzhou China
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17
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Li ZQ, Tang JH, Zhong YW. Multidentate Anchors for Surface Functionalization. Chem Asian J 2019; 14:3119-3126. [PMID: 31389657 DOI: 10.1002/asia.201900989] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 08/06/2019] [Indexed: 01/01/2023]
Abstract
The bottom-up functionalization of solid surfaces shows increasing importance for a wide range of interdisciplinary applications. Multidentate anchors with more than two contact points can bind to solid surfaces with strong chemisorption, well-defined upright configuration, and tailored functionality. The surface functionalization using multidentate anchors with three (tripodal), four (quadripodal), or more binding points is summarized herein, with a focus on those beyond classical tripodal anchors. In particular, the molecular design on how to achieve multisite interaction between anchor and substrate and the introduction of functional groups to thin films are discussed.
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Affiliation(s)
- Zhong-Qiu Li
- Key Laboratory of Photochemistry, Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 2 Bei Yi Jie, Zhong Guan Cun, Haidian District, Beijing, 100190, China.,School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jian-Hong Tang
- Key Laboratory of Photochemistry, Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 2 Bei Yi Jie, Zhong Guan Cun, Haidian District, Beijing, 100190, China
| | - Yu-Wu Zhong
- Key Laboratory of Photochemistry, Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 2 Bei Yi Jie, Zhong Guan Cun, Haidian District, Beijing, 100190, China.,School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
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18
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Herrer L, Ismael A, Martín S, Milan DC, Serrano JL, Nichols RJ, Lambert C, Cea P. Single molecule vs. large area design of molecular electronic devices incorporating an efficient 2-aminepyridine double anchoring group. NANOSCALE 2019; 11:15871-15880. [PMID: 31414113 DOI: 10.1039/c9nr05662a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
When a molecule is bound to external electrodes by terminal anchor groups, the latter are of paramount importance in determining the electrical conductance of the resulting molecular junction. Here we explore the electrical properties of a molecule with bidentate anchor groups, namely 4,4'-(1,4-phenylenebis(ethyne-2,1-diyl))bis(pyridin-2-amine), in both large area devices and at the single molecule level. We find an electrical conductance of 0.6 × 10-4G0 and 1.2 × 10-4G0 for the monolayer and for the single molecule, respectively. These values are approximately one order of magnitude higher than those reported for monodentate materials having the same molecular skeleton. A combination of theory and experiments is employed to understand the conductance of monolayer and single molecule electrical junctions featuring this new multidentate anchor group. Our results demonstrate that the molecule has a tilt angle of 30° with respect to the normal to the surface in the monolayer, while the break-off length in the single molecule junction occurs for molecules having a tilt angle estimated as 40°, which would account for the difference in their conductance values per molecule. The bidentate 2-aminepyridine anchor is of general interest as a contact group, since this terminal functionalized aromatic ring favours binding of the adsorbate to the metal contact resulting in enhanced conductance values.
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Affiliation(s)
- L Herrer
- Departamento de Química Física, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain. and Instituto de Nanociencia de Aragón (INA) and Laboratorio de Microscopias Avanzadas (LMA), Edificio I+D Campus Río Ebro, Universidad de Zaragoza, C/Mariano Esquillor, s/n, 50018 Zaragoza, Spain.
| | - A Ismael
- Department of Physics, University of Lancaster, Lancaster, LA1 4YB, UK. and Department of Physics, College of Education for Pure Science, Tikrit University, Tikrit, Iraq
| | - S Martín
- Departamento de Química Física, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain. and Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK.
| | - D C Milan
- Instituto de Ciencia de Materiales de Aragón (ICMA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - J L Serrano
- Instituto de Nanociencia de Aragón (INA) and Laboratorio de Microscopias Avanzadas (LMA), Edificio I+D Campus Río Ebro, Universidad de Zaragoza, C/Mariano Esquillor, s/n, 50018 Zaragoza, Spain. and Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK. and Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain
| | - R J Nichols
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK.
| | - C Lambert
- Department of Physics, University of Lancaster, Lancaster, LA1 4YB, UK.
| | - P Cea
- Departamento de Química Física, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain. and Instituto de Nanociencia de Aragón (INA) and Laboratorio de Microscopias Avanzadas (LMA), Edificio I+D Campus Río Ebro, Universidad de Zaragoza, C/Mariano Esquillor, s/n, 50018 Zaragoza, Spain. and Instituto de Ciencia de Materiales de Aragón (ICMA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
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19
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Šebera J, Lindner M, Gasior J, Mészáros G, Fuhr O, Mayor M, Valášek M, Kolivoška V, Hromadová M. Tuning the contact conductance of anchoring groups in single molecule junctions by molecular design. NANOSCALE 2019; 11:12959-12964. [PMID: 31259338 DOI: 10.1039/c9nr04071d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A tetraphenylmethane tripod functionalized with three thiol moieties in the para position can serve as a supporting platform for functional molecular electronic elements. A combined experimental scanning tunneling microscopy break junction technique with theoretical approaches based on density functional theory and non-equilibrium Green's function formalism was used for detailed charge transport analysis to find configurations, geometries and charge transport pathways in the molecular junctions of single molecule oligo-1,4-phenylene conductors containing this tripodal anchoring group. The effect of molecular length (n = 1 to 4 repeating phenylene units) on the charge transport properties and junction configurations is addressed. The number of covalent attachments between the electrode and the tripodal platform changes with n affecting the contact conductance of the junction. The longest homologue n = 4 adopts an upright configuration with all three para thiolate moieties of the tripod attached to the gold electrode. The contact conductance of the tetraphenylmethane tripod substituted by thiols in the para position is higher than that substituted in the meta position. Such molecular arrangement is highly conducting and allows well-defined directional positioning of a variety of functional groups.
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Affiliation(s)
- Jakub Šebera
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic.
| | - Marcin Lindner
- Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology, P. O. Box 3640, 76021 Karlsruhe, Germany.
| | - Jindřich Gasior
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic.
| | - Gábor Mészáros
- Research Centre for Natural Sciences, HAS, Magyar tudósok krt. 2, H-1117 Budapest, Hungary
| | - Olaf Fuhr
- Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology, P. O. Box 3640, 76021 Karlsruhe, Germany.
| | - Marcel Mayor
- Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology, P. O. Box 3640, 76021 Karlsruhe, Germany. and Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Michal Valášek
- Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology, P. O. Box 3640, 76021 Karlsruhe, Germany.
| | - Viliam Kolivoška
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic.
| | - Magdaléna Hromadová
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic.
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20
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Homberg J, Lindner M, Gerhard L, Edelmann K, Frauhammer T, Nahas Y, Valášek M, Mayor M, Wulfhekel W. Six state molecular revolver mounted on a rigid platform. NANOSCALE 2019; 11:9015-9022. [PMID: 31020977 DOI: 10.1039/c9nr00259f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The rotation of entire molecules or large moieties happens at 100 ps time scales and the transition process itself is experimentally inaccessible to scanning probe techniques. However, the reversible switching of a molecule between more than two metastable states allows to assign a rotational switching direction. Rotational switching is a phenomenon that is particularly interesting with regard to possible applications in molecular motors. In this work, single tetraphenylmethane molecules deposited on a Au(111) surface were studied in a low temperature scanning tunneling microscope (STM). These molecules comprise rotational axes mounted on a tripodal sulfur-anchored stand and with the STM tip, we were able to induce transitions between six rotational states of the molecular motif. We were able to identify critical parameters for the onset of rotational switching and to characterize the influence of the local environment. The subtle difference between fcc and hcp stacking and the rotational state of neighboring molecules clearly influence the population of the rotational states.
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Affiliation(s)
- Jan Homberg
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany.
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21
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Freibert A, Dieterich JM, Hartke B. Exploring self-organization of molecular tether molecules on a gold surface by global structure optimization. J Comput Chem 2019; 40:1978-1989. [PMID: 31069834 DOI: 10.1002/jcc.25853] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 04/16/2019] [Accepted: 04/22/2019] [Indexed: 11/11/2022]
Abstract
We employ nondeterministic global cluster structure optimization, based on the evolutionary algorithms paradigm, to model the self-assembly of complex molecules on a surface. As a real-life application example directly related to many recent experiments, we use this approach for the assembly of triazatriangulene "platform" molecules on the Au(111) surface. Without additional restrictions like spatial discretizations, coarse-graining or precalculated adsorption poses, and despite the proof-of-principle character of this study, we achieve satisfactory qualitative agreement with several experimental observations and can provide answers to questions that experiments on these species had left open so far. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Antonia Freibert
- Institute for Physical Chemistry, Christian-Albrechts-University, Olshausenstr. 40, 24098, Kiel, Germany.,Department of Chemistry, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - Johannnes M Dieterich
- Institute for Physical Chemistry, Christian-Albrechts-University, Olshausenstr. 40, 24098, Kiel, Germany
| | - Bernd Hartke
- Institute for Physical Chemistry, Christian-Albrechts-University, Olshausenstr. 40, 24098, Kiel, Germany
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22
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Jasper-Tönnies T, Garcia-Lekue A, Frederiksen T, Ulrich S, Herges R, Berndt R. High-conductance contacts to functionalized molecular platforms physisorbed on Au(1 1 1). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:18LT01. [PMID: 30721893 DOI: 10.1088/1361-648x/ab0489] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The conductances of molecules physisorbed to Au(1 1 1) via an extended [Formula: see text] system are probed with the tip of a low-temperature scanning tunneling microscope to maximize the control of the junction geometry. Inert hydrogen, methyl, and reactive propynyl subunits were attached to the platform and stand upright. Because of their different reactivities, either non-bonding (hydrogen and methyl) or bonding (propynyl) tip-molecule contacts are formed. The conductances exhibit little scatter between different experimental runs on different molecules, display distinct evolutions with the tip-subunit distance, and reach contact values of 0.003-0.05 G 0. For equal tip-platform distances the contact conductance of the inert methyl is close to that of the reactive propynyl. Under further compression, the inert species, hydrogen and methyl, are found to be better conductors. This shows that the current flow is not directly correlated with the chemical interaction. Atomistic calculations for the methyl case reproduce the conductance evolution and reveal the role of the junction geometry, forces and orbital symmetries at the tip-molecule interface. The current flow is controlled by orbital symmetries at the electrode interfaces rather than by the energy alignment of the molecular orbitals and electrode states. Functionalized molecular platforms thus open new ways to control and engineer electron conduction through metal-molecule interfaces at the atomic level.
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Affiliation(s)
- Torben Jasper-Tönnies
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098 Kiel, Germany
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23
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Ishiwari F, Nascimbeni G, Sauter E, Tago H, Shoji Y, Fujii S, Kiguchi M, Tada T, Zharnikov M, Zojer E, Fukushima T. Triptycene Tripods for the Formation of Highly Uniform and Densely Packed Self-Assembled Monolayers with Controlled Molecular Orientation. J Am Chem Soc 2019; 141:5995-6005. [PMID: 30869881 PMCID: PMC6483319 DOI: 10.1021/jacs.9b00950] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
![]()
When
employing self-assembled monolayers (SAMs) for tuning surface
and interface properties, organic molecules that enable strong binding
to the substrate, large-area structural uniformity, precise alignment
of functional groups, and control of their density are highly desirable.
To achieve these goals, tripod systems bearing multiple bonding sites
have been developed as an alternative to conventional monodentate
systems. Bonding of all three sites has, however, hardly been achieved,
with the consequence that structural uniformity and orientational
order in tripodal SAMs are usually quite poor. To overcome that problem,
we designed 1,8,13-trimercaptomethyltriptycene (T1) and
1,8,13-trimercaptotriptycene (T2) as potential tripodal
SAM precursors and investigated their adsorption behavior on Au(111)
combining several advanced experimental techniques and state-of-the-art
theoretical simulations. Both SAMs adopt dense, nested hexagonal structures
but differ in their adsorption configurations and structural uniformity.
While the T2-based SAM exhibits a low degree of order
and noticeable deviation from the desired tripodal anchoring, all
three anchoring groups of T1 are equally bonded to the
surface as thiolates, resulting in an almost upright orientation of
the benzene rings and large-area structural uniformity. These superior
properties are attributed to the effect of conformationally flexible
methylene linkers at the anchoring groups, absent in the case of T2. Both SAMs display interesting electronic properties, and,
bearing in mind that the triptycene framework can be functionalized
by tail groups in various positions and with high degree of alignment,
especially T1 appears as an ideal docking platform for
complex and highly functional molecular films.
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Affiliation(s)
| | - Giulia Nascimbeni
- Institute of Solid State Physics, NAWI Graz , Graz University of Technology , Petersgasse 16 , Graz 8010 , Austria
| | - Eric Sauter
- Applied Physical Chemistry , Heidelberg University , Im Neuenheimer Feld 253 , Heidelberg 69120 , Germany
| | | | | | - Shintaro Fujii
- Department of Chemistry, Graduate School of Science and Engineering , Tokyo Institute of Technology , Meguro , Tokyo 152-8551 , Japan
| | - Manabu Kiguchi
- Department of Chemistry, Graduate School of Science and Engineering , Tokyo Institute of Technology , Meguro , Tokyo 152-8551 , Japan
| | | | - Michael Zharnikov
- Applied Physical Chemistry , Heidelberg University , Im Neuenheimer Feld 253 , Heidelberg 69120 , Germany
| | - Egbert Zojer
- Institute of Solid State Physics, NAWI Graz , Graz University of Technology , Petersgasse 16 , Graz 8010 , Austria
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24
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Kolivoška V, Šebera J, Sebechlebská T, Lindner M, Gasior J, Mészáros G, Mayor M, Valášek M, Hromadová M. Probabilistic mapping of single molecule junction configurations as a tool to achieve the desired geometry of asymmetric tripodal molecules. Chem Commun (Camb) 2019; 55:3351-3354. [PMID: 30815643 DOI: 10.1039/c8cc09681c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Four molecules containing identical tripodal anchors and p-oligophenylene molecular wires of increasing length were used to demonstrate tuning of the asymmetric molecular junction to the desired geometry by probabilistic mapping of single molecule junction configurations in a scanning tunnelling microscopy break junction experiment.
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Affiliation(s)
- Viliam Kolivoška
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic.
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25
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Rusch TR, Hammerich M, Herges R, Magnussen OM. Molecular platforms as versatile building blocks for multifunctional photoswitchable surfaces. Chem Commun (Camb) 2019; 55:9511-9514. [DOI: 10.1039/c9cc04528g] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Structurally well-defined arrangements of multiple functional groups can be prepared by self-assembly of mixed monolayers based on molecular platforms.
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Affiliation(s)
- Talina R. Rusch
- Institute of Experimental and Applied Physics
- Kiel University
- Kiel
- Germany
| | | | - Rainer Herges
- Otto Diels Institute of Organic Chemistry
- Kiel University
- Kiel
- Germany
| | - Olaf M. Magnussen
- Institute of Experimental and Applied Physics
- Kiel University
- Kiel
- Germany
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26
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Jasper-Tönnies T, Poltavsky I, Ulrich S, Moje T, Tkatchenko A, Herges R, Berndt R. Stability of functionalized platform molecules on Au(111). J Chem Phys 2018; 149:244705. [PMID: 30599747 DOI: 10.1063/1.5059344] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Trioxatriangulenium (TOTA) platform molecules were functionalized with methyl, ethyl, ethynyl, propynyl, and hydrogen and sublimated onto Au(111) surfaces. Low-temperature scanning tunneling microscopy data reveal that >99% of ethyl-TOTA and methyl-TOTA remain intact, whereas 60% of H-TOTA and >99% of propynyl-TOTA and ethynyl-TOTA decompose. The observed tendency toward fragmentation on Au(111) is opposite to the sequence of gas-phase stabilities of the molecules. Although Au(111) is the noblest of all metal surfaces, the binding energies of the decomposition products to Au(111) destabilize the functionalized platforms by 2 to 3.9 eV (190-370 kJ/mol) and even render some of them unstable as revealed by density functional theory calculations. Van der Waals forces are important, as they drive the adsorption of the platform molecules.
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Affiliation(s)
- Torben Jasper-Tönnies
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Igor Poltavsky
- Physics and Materials Science Research Unit, University of Luxembourg, Luxembourg City L-1511, Luxembourg
| | - Sandra Ulrich
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Tobias Moje
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Alexandre Tkatchenko
- Physics and Materials Science Research Unit, University of Luxembourg, Luxembourg City L-1511, Luxembourg
| | - Rainer Herges
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
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Ivleva EA, Baimuratov MR, Pogulyaiko AV, Malinovskaya AA, Kulikova IA, Tyshchenko VA, Pozdnyakov VV, Ovchinnikov KA, Klimochkin YN. Synthesis, Physicochemical Properties, and Thermo-Oxidative Stability of Diesters of 5,7-Dimethyl-3-hydroxymethyl-1-adamantanol. RUSS J GEN CHEM+ 2018. [DOI: 10.1134/s1070363218080091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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