1
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Lawson B, Vidal E, Luna S, Haley MM, Kamenetska M. Extreme Anomalous Conductance Enhancement in Neutral Diradical Acene-like Molecular Junctions. ACS NANO 2024. [PMID: 39392333 DOI: 10.1021/acsnano.4c10183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/12/2024]
Abstract
We achieve, at room temperature, conductance enhancements over 2 orders of magnitude in single molecule circuits formed with polycyclic benzoquinoidal (BQn) diradicals upon increasing molecular length by ∼5 Å. We find that this extreme and atypical anti-ohmic conductance enhancement at longer molecular lengths is due to the diradical character of the molecules, which can be described as a topologically nontrivial electronic state, and results in constructive interference between the frontier molecular orbitals. The distinct feature of the compounds studied here as molecular wires is that they are characterized by moderate diradical character in the neutral state, allowing for robust and facile measurements of their transport properties. We adapt the 1D-SSH model, originally developed to examine electronic topological order in linear carbon chains, to the polycyclic systems studied here and find that it captures the anti-ohmic trends in this molecular series. Specifically, our model reveals that the mechanism of conductance enhancement with length in polycyclic systems is constructive quantum interference between the frontier orbitals with nontrivial topology, which is present in acene-like, but not in linear, molecular systems. Importantly, we use our model to predict and experimentally validate that anti-ohmic trends can be engineered through synthetic adjustments of the diradical character of the acene-like molecules. Overall, we achieve extreme anti-ohmic enhancement and mechanistic insight into electronic transport in a class of materials that we identify here as promising candidates for creating highly conductive and tunable nanoscale wires.
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Affiliation(s)
- Brent Lawson
- Department of Physics, Boston University, Boston, Massachusetts 02215, United States
| | - Efrain Vidal
- Department of Chemistry & Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
- Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Sigifredo Luna
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
| | - Michael M Haley
- Department of Chemistry & Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
- Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Maria Kamenetska
- Department of Physics, Boston University, Boston, Massachusetts 02215, United States
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
- Division of Material Science and Engineering, Boston University, Boston, Massachusetts 02215, United States
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2
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Miyashita T, He S, Jaimes P, Kaledin AL, Fumanal M, Lian T, Lee Tang M. Oligoyne bridges enable strong through-bond coupling and efficient triplet transfer from CdSe QD trap excitons for photon upconversion. J Chem Phys 2024; 161:094707. [PMID: 39234973 DOI: 10.1063/5.0223478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2024] [Accepted: 08/12/2024] [Indexed: 09/06/2024] Open
Abstract
Polyyne bridges have attracted extensive interest as molecular wires due to their shallow distance dependence during charge transfer. Here, we investigate whether triplet energy transfer from cadmium selenide (CdSe) quantum dots (QDs) to anthracene acceptors benefits from the high conductance associated with polyyne bridges, especially from the potential cumulene character in their excited states. Introducing π-electron rich oligoyne bridges between the surface-bound anthracene-based transmitter ligands, we explore the triplet energy transfer rate between the CdSe QDs and anthracene core. Our femtosecond transient absorption results reveal that a rate constant damping coefficient of β is 0.118 ± 0.011 Å-1, attributed to a through-bond coupling mechanism facilitated by conjugation among the anthracene core, the oligoyne bridges, and the COO⊖ anchoring group. In addition, oligoyne bridges lower the T1 energy level of the anthracene-based transmitters, enabling efficient triplet energy transfer from trapped excitons in CdSe QDs. Density-functional theory calculations suggest a slight cumulene character in these oligoyne bridges during triplet energy transfer, with diminished bond length alternation. This work demonstrates the potential of oligoyne bridges in mediating long-distance energy transfer.
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Affiliation(s)
- Tsumugi Miyashita
- Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah 84112, USA
| | - Sheng He
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA
| | - Paulina Jaimes
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Alexey L Kaledin
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA
- The Cherry L. Emerson Center for Scientific Computation, Emory University, 1515 Dickey Drive Northeast, Atlanta, Georgia 30322, USA
| | - Maria Fumanal
- Departament de Ciència de Materials i Química Física and IQTCUB, Facultat de Química, Universitat de Barcelona, Martí i Franquès 1, E-08028 Barcelona, Spain
| | - Tianquan Lian
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA
| | - Ming Lee Tang
- Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah 84112, USA
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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3
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Gustafson A, Sburlati S, Kahr B. Computed Gyration Tensors of Knotted Chiral and Achiral Topological Stereoisomers of C 60 Cyclocarbons. Chemphyschem 2024; 25:e202400277. [PMID: 38606486 DOI: 10.1002/cphc.202400277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/10/2024] [Accepted: 04/10/2024] [Indexed: 04/13/2024]
Abstract
The electronic origins of the computed optical rotations of the simplest chiral and achiral chemical knots with comparatively simple compositions and large, anticipated magnetoelectric polarizabilities are provided. Linear response theory (LRT) is used to calculate the gyration at 1064 nm of two knotted polyyne chains, topological stereoisomers of cyclo[60]carbon. One isomer is analogous to the trefoil knot with approximate D3 symmetry and the other to the figure eight knot with approximate S4 symmetry. The response in each case can be attributed largely to the magnetic dipole term that arises in a near degenerate E-like excited state. An oriented achiral figure eight knot is as optically active in some directions as the chiral knot in any direction, and its absolute eigenvalues are larger.
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Affiliation(s)
- Afton Gustafson
- Department of Chemistry and Molecular Design Institute, New York University, 100 Washington Square East, Room 1001, New York City, New York, 10003, USA
| | - Sophia Sburlati
- Department of Chemistry and Molecular Design Institute, New York University, 100 Washington Square East, Room 1001, New York City, New York, 10003, USA
| | - Bart Kahr
- Department of Chemistry and Molecular Design Institute, New York University, 100 Washington Square East, Room 1001, New York City, New York, 10003, USA
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4
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Li L, Louie S, Orchanian NM, Nuckolls C, Venkataraman L. Long-Range Gating in Single-Molecule One-Dimensional Topological Insulators. J Am Chem Soc 2024. [PMID: 38832840 DOI: 10.1021/jacs.4c05699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
Single-molecule one-dimensional topological insulator (1D TI) is a class of molecular wires that exhibit increasing conductance with wire length. This unique trend is due to the coupling between the two low-lying topological edge states of 1D TIs described by the Su-Schrieffer-Heeger model. In principle, this quantum phenomenon within 1D TIs can be utilized to achieve long-range gating in molecular conductors. Here, we study electron transport through a single-edge state of doubly oxidized oligophenylene bis(triarylamine) to understand the effect of the edge state coupling on conductance. We find that conductance is elevated by approximately 1 order of magnitude compared to a control molecule with the same conductance pathway. Density function theory calculations further support that the increase in conductance is due to the interaction between the edge states of 1D TIs. This work demonstrates a new gating paradigm in molecular electronics, while also providing a deeper understanding of how edge states interact and affect electron transport within 1D TIs.
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Affiliation(s)
- Liang Li
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Shayan Louie
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Nicholas M Orchanian
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Latha Venkataraman
- Department of Chemistry, Columbia University, New York, New York 10027, United States
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
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5
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Zhou Z, Johnson MA, Wei Z, Bühringer MU, Garner MH, Tykwinski R, Petrukhina MA. Bending a Cumulene with Electrons: Stepwise Chemical Reduction and Structural Study of a Tetraaryl[4]Cumulene. Chemistry 2024; 30:e202304145. [PMID: 38433113 DOI: 10.1002/chem.202304145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/02/2024] [Accepted: 03/03/2024] [Indexed: 03/05/2024]
Abstract
Chemical reduction of a [4]cumulene with cesium metal was explored, and the structural changes stemming from electron acquisition are detailed using X-ray crystallography. It is found that the [4]cumulene undergoes dramatic geometric changes upon stepwise reduction, including bending of the cumulenic core and twisting of the endgroups from orthogonal to planar. The structural deformation is consistent with early theoretical reports that suggest that the twisting should occur upon reduction of both even and odd [n]cumulenes. The current results, on the other hand, are inconsistent with a previous experimental study of a [3]cumulene in which the predicted twisting is not observed upon reduction. DFT calculations reveal that the barrier to deformation is an order of magnitude lower in a [3]cumulene than a [4]cumulene, allowing the barrier to be overcome in the solid-state.
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Affiliation(s)
- Zheng Zhou
- Department of Chemistry, University at Albany, State University of New York, Albany, NY-12222, USA
| | - Matthew A Johnson
- Department of Chemistry, University of Alberta, Edmonton, AB-T6G 2G2, Canada
| | - Zheng Wei
- Department of Chemistry, University at Albany, State University of New York, Albany, NY-12222, USA
| | - Martina U Bühringer
- Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Nikolaus-Fiebiger Str. 10, 91058, Erlangen, Germany
| | - Marc H Garner
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Rik Tykwinski
- Department of Chemistry, University of Alberta, Edmonton, AB-T6G 2G2, Canada
| | - Marina A Petrukhina
- Department of Chemistry, University at Albany, State University of New York, Albany, NY-12222, USA
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6
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Deng JR, González MT, Zhu H, Anderson HL, Leary E. Ballistic Conductance through Porphyrin Nanoribbons. J Am Chem Soc 2024; 146:3651-3659. [PMID: 38301131 PMCID: PMC10870699 DOI: 10.1021/jacs.3c07734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 11/22/2023] [Accepted: 11/22/2023] [Indexed: 02/03/2024]
Abstract
The search for long molecular wires that can transport charge with maximum efficiency over many nanometers has driven molecular electronics since its inception. Single-molecule conductance normally decays with length and is typically far below the theoretical limit of G0 (77.5 μS). Here, we measure the conductances of a family of edge-fused porphyrin ribbons (lengths 1-7 nm) that display remarkable behavior. The low-bias conductance is high across the whole series. Charging the molecules in situ results in a dramatic realignment of the frontier orbitals, increasing the conductance to 1 G0 (corresponding to a current of 20 μA). This behavior is most pronounced in the longer molecules due to their smaller HOMO-LUMO gaps. The conductance-voltage traces frequently exhibit peaks at zero bias, showing that a molecular energy level is in resonance with the Fermi level. This work lays the foundations for long, perfectly transmissive, molecular wires with technological potential.
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Affiliation(s)
- Jie-Ren Deng
- Department
of Chemistry, Chemistry Research Laboratory, Oxford University, Oxford OX1 3TA, U.K.
| | - M. Teresa González
- Fundación
IMDEA Nanociencia, Calle
Faraday 9, Campus de Cantoblanco, 28049 Madrid, Spain
| | - He Zhu
- Department
of Chemistry, Chemistry Research Laboratory, Oxford University, Oxford OX1 3TA, U.K.
| | - Harry L. Anderson
- Department
of Chemistry, Chemistry Research Laboratory, Oxford University, Oxford OX1 3TA, U.K.
| | - Edmund Leary
- Fundación
IMDEA Nanociencia, Calle
Faraday 9, Campus de Cantoblanco, 28049 Madrid, Spain
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7
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Marongiu M, Ha T, Gil-Guerrero S, Garg K, Mandado M, Melle-Franco M, Diez-Perez I, Mateo-Alonso A. Molecular Graphene Nanoribbon Junctions. J Am Chem Soc 2024; 146:3963-3973. [PMID: 38305745 PMCID: PMC10870704 DOI: 10.1021/jacs.3c11340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/20/2023] [Accepted: 01/12/2024] [Indexed: 02/03/2024]
Abstract
One of the challenges for the realization of molecular electronics is the design of nanoscale molecular wires displaying long-range charge transport. Graphene nanoribbons are an attractive platform for the development of molecular wires with long-range conductance owing to their unique electrical properties. Despite their potential, the charge transport properties of single nanoribbons remain underexplored. Herein, we report a synthetic approach to prepare N-doped pyrene-pyrazinoquinoxaline molecular graphene nanoribbons terminated with diamino anchoring groups at each end. These terminal groups allow for the formation of stable molecular graphene nanoribbon junctions between two metal electrodes that were investigated by scanning tunneling microscope-based break-junction measurements. The experimental and computational results provide evidence of long-range tunneling charge transport in these systems characterized by a shallow conductance length dependence and electron tunneling through >6 nm molecular backbone.
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Affiliation(s)
- Mauro Marongiu
- POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018 Donostia-San Sebastian, Spain
| | - Tracy Ha
- Department
of Chemistry, Faculty of Natural & Mathematical Sciences, King’s College London, Britannia House, 7 Trinity Street, SE1 1DB London, United Kingdom
| | - Sara Gil-Guerrero
- CICECO—Aveiro
Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Kavita Garg
- Department
of Chemistry, Faculty of Natural & Mathematical Sciences, King’s College London, Britannia House, 7 Trinity Street, SE1 1DB London, United Kingdom
| | - Marcos Mandado
- Department
of Physical Chemistry, University of Vigo, Lagoas-Marcosende s/n, 36310 Vigo, Spain
| | - Manuel Melle-Franco
- CICECO—Aveiro
Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Ismael Diez-Perez
- Department
of Chemistry, Faculty of Natural & Mathematical Sciences, King’s College London, Britannia House, 7 Trinity Street, SE1 1DB London, United Kingdom
| | - Aurelio Mateo-Alonso
- POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018 Donostia-San Sebastian, Spain
- Ikerbasque, Basque
Foundation for Science, 48009 Bilbao, Spain
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8
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Guo MM, Jiang Y, Wang JY, Chen ZN, Hou S, Zhang QC. Effectively Enhancing the Conductance of Asymmetric Molecular Wires by Aligning the Energy Level and Symmetrizing the Coupling. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024. [PMID: 38332611 DOI: 10.1021/acs.langmuir.3c03530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
An asymmetric structure is an important strategy for designing highly conductive molecular wires for a gap-fixed molecular circuit. As the conductance enhancement in the current strategy is still limited to about 2 times, we inserted a methylene group as a spacer in a conjugated structure to modulate the structural symmetry. We found that the conductance drastically enhanced in the asymmetric molecular wire to 1.5 orders of magnitude as high as that in the symmetric molecular wire. First-principles quantum transport studies attributed the effective enhancement to the synchronization of improved energy alignment and nearly symmetric coupling between the frontier orbitals and the electrodes.
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Affiliation(s)
- Meng-Meng Guo
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China
| | - Yuxuan Jiang
- Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing 100871, People's Republic of China
- Centre for Nanoscale Science and Technology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, People's Republic of China
| | - Jin-Yun Wang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China
| | - Zhong-Ning Chen
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China
| | - Shimin Hou
- Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing 100871, People's Republic of China
- Centre for Nanoscale Science and Technology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, People's Republic of China
| | - Qian-Chong Zhang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China
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9
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Li L, Prindle CR, Shi W, Nuckolls C, Venkataraman L. Radical Single-Molecule Junctions. J Am Chem Soc 2023; 145:18182-18204. [PMID: 37555594 DOI: 10.1021/jacs.3c04487] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
Radicals are unique molecular systems for applications in electronic devices due to their open-shell electronic structures. Radicals can function as good electrical conductors and switches in molecular circuits while also holding great promise in the field of molecular spintronics. However, it is both challenging to create stable, persistent radicals and to understand their properties in molecular junctions. The goal of this Perspective is to address this dual challenge by providing design principles for the synthesis of stable radicals relevant to molecular junctions, as well as offering current insight into the electronic properties of radicals in single-molecule devices. By exploring both the chemical and physical properties of established radical systems, we will facilitate increased exploration and development of radical-based molecular systems.
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Affiliation(s)
- Liang Li
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Claudia R Prindle
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Wanzhuo Shi
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Latha Venkataraman
- Department of Chemistry, Columbia University, New York, New York 10027, United States
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
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10
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Hou SJ, Yang YF, Cui ZH, Cederbaum LS. Can anions possess bound doubly-excited electronic states? Chem Sci 2023; 14:7230-7236. [PMID: 37416703 PMCID: PMC10321500 DOI: 10.1039/d3sc00370a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 05/27/2023] [Indexed: 07/08/2023] Open
Abstract
Anions play an important role in many fields of chemistry. Many molecules possess stable anions, but these anions often do not have stable electronic excited states and the anion loses its excess electron once excited. All the known stable valence excited states of anions are singly-excited states, i.e., valence doubly-excited states have not been reported. As excited states are relevant for numerous applications, and constitute basic properties, we searched for valence doubly-excited states which are stable, i.e., exhibit energies below that of the ground state of the respective neutral molecule. We concentrated on two promising prototype candidates, the anions of the smallest endocircular carbon ring Li@C12 and of the smallest endohedral fullerene Li@C20. By employing accurate state-of-the-art many-electron quantum chemistry methods, we investigated the low-lying excited states of these anions and found that they possess several low-lying stable singly-excited states and, in particular, a stable doubly-excited state each. It is noteworthy that the found doubly-excited state of Li@C12- possesses a cumulenic carbon ring in sharp contrast to the ground and singly-excited states. The findings shed light on how to design anions with stable valence singly- and doubly-excited states. Possible applications are mentioned.
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Affiliation(s)
- Shi-Jie Hou
- Institute of Atomic and Molecular Physics, Jilin University Changchun 130023 China
| | - Yi-Fan Yang
- Quantum Theory Project, Departments of Physics and Chemistry, University of Florida Gainesville Florida 32611 USA
| | - Zhong-Hua Cui
- Institute of Atomic and Molecular Physics, Jilin University Changchun 130023 China
| | - Lorenz S Cederbaum
- Theoretical Chemistry, Institute of Physical Chemistry, Universität Heidelberg Im Neuenheimer Feld 229 D-69120 Heidelberg Germany
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11
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Wang M, Chen X, Lu W, Tian X, Zhang GP. Silver electrodes provide higher conductance than gold for thiol-terminated oligosilane molecular junctions: the interfacial effect. Phys Chem Chem Phys 2023; 25:13673-13682. [PMID: 37158005 DOI: 10.1039/d2cp06030b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The understanding of the interfacial effect on charge transport is essential in single-molecule electronics. In this study, we elucidated the transport properties of molecular junctions comprising thiol-terminated oligosilane with three to eight Si atoms and two types of Ag/Au electrode materials employing different interfacial configurations. First-principles quantum transport calculations demonstrated that the interfacial configuration determines the relative magnitude of the current between the Ag and Au electrodes, wherein the Ag monoatomic contact configuration presented a larger current than did the Au double-atom configuration. Further, the mechanism of electron tunneling from the interfacial states through the central σ channel was revealed. In contrast to Au double-atom electrodes, Ag monoatomic electrodes exhibit a higher current due to the presence of Ag-S interfacial states closer to the Fermi level. Our findings show that the interfacial configuration is a plausible way to generate the relative magnitude of current of thiol-terminated oligosilane molecular junctions with Au/Ag electrodes and provide further insight into the interfacial effect on the transport properties.
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Affiliation(s)
- Minglang Wang
- Shandong Key Laboratory of Medical Physics and Image Processing & Shandong Provincial Engineering and Technical Center of Light Manipulations, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China.
| | - Xianglin Chen
- Shandong Key Laboratory of Medical Physics and Image Processing & Shandong Provincial Engineering and Technical Center of Light Manipulations, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China.
| | - Wenjun Lu
- Shandong Key Laboratory of Medical Physics and Image Processing & Shandong Provincial Engineering and Technical Center of Light Manipulations, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China.
| | - Xinyue Tian
- Shandong Key Laboratory of Medical Physics and Image Processing & Shandong Provincial Engineering and Technical Center of Light Manipulations, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China.
| | - Guang-Ping Zhang
- Shandong Key Laboratory of Medical Physics and Image Processing & Shandong Provincial Engineering and Technical Center of Light Manipulations, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China.
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12
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Gorenskaia E, Potter J, Korb M, Lambert C, Low PJ. Exploring relationships between chemical structure and molecular conductance: from α,ω-functionalised oligoynes to molecular circuits. NANOSCALE 2023. [PMID: 37070423 DOI: 10.1039/d3nr01034a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The quantum circuit rule (QCR) allows estimation of the conductance of molecular junctions, electrode|X-bridge-Y|electrode, by considering the molecule as a series of independent scattering regions associated with the anchor groups (X, Y) and bridge, provided the numerical parameters that characterise the anchor groups (aX, aY) and molecular backbones (bB) are known. Single-molecule conductance measurements made with a series of α,ω-substituted oligoynes (X-{(CC)N}-X, N = 1, 2, 3, 4), functionalised by terminal groups, X (4-thioanisole (C6H4SMe), 5-(3,3-dimethyl-2,3-dihydrobenzo[b]thiophene) (DMBT), 4-aniline (C6H4NH2), 4-pyridine (Py), capable of serving as 'anchor groups' to contact the oligoyne fragment within a molecular junction, have shown the expected exponential dependence of molecular conductance, G, with the number of alkyne repeating units. In turn, this allows estimation of the anchor (ai) and backbone (bi) parameters. Using these values, together with previously determined parameters for other molecular fragments, the QCR is found to accurately estimate the junction conductance of more complex molecular circuits formed from smaller components assembled in series.
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Affiliation(s)
- Elena Gorenskaia
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6026, Australia.
| | - Jarred Potter
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6026, Australia.
| | - Marcus Korb
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6026, Australia.
| | - Colin Lambert
- Department of Physics, University of Lancaster, Lancaster LA1 4YB, England, UK.
| | - Paul J Low
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6026, Australia.
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13
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Bajaj A, Ali ME. Anti-ohmic nanoconductors: myth, reality and promise. Phys Chem Chem Phys 2023; 25:9607-9616. [PMID: 36942699 DOI: 10.1039/d3cp00366c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
The recent accomplishment in the design of molecular nanowires characterized by increasing conductance with length has led to the origin of an extraordinary new family of molecular junctions referred to as "anti-ohmic" wires. Herein, this highly desirable, non-classical behavior, has been examined for molecules long-enough to exhibit pronounced diradical character in their ground state within the unrestricted DFT formalism with spin symmetry breaking. We demonstrate that highly conjugated acenes signal higher resistance in an open-shell singlet (OSS) configuration as compared to their closed-shell counterparts. This anomaly has been further proven for experimentally certified cumulene wires, which reveals phenomenal modulation in the transport characteristics such that an increasing conductance is observed in the closed-shell limit, while higher cumulenes in the OSS ground state yield regular decay of conductance.
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Affiliation(s)
- Ashima Bajaj
- Institute of Nano Science and Technology, Sector-81, Mohali, Punjab-140306, India.
| | - Md Ehesan Ali
- Institute of Nano Science and Technology, Sector-81, Mohali, Punjab-140306, India.
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14
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Mang A, Rotthowe N, Beltako K, Linseis M, Pauly F, Winter RF. Single-molecule conductance studies on quasi- and metallaaromatic dibenzoylmethane coordination compounds and their aromatic analogs. NANOSCALE 2023; 15:5305-5316. [PMID: 36811332 DOI: 10.1039/d2nr05670d] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The ability to predict the conductive behaviour of molecules, connected to macroscopic electrodes, represents a crucial prerequisite for the design of nanoscale electronic devices. In this work, we investigate whether the notion of a negative relation between conductance and aromaticity (the so-called NRCA rule) also pertains to quasi-aromatic and metallaaromatic chelates derived from dibenzoylmethane (DBM) and Lewis acids (LAs) that either do or do not contribute two extra dπ electrons to the central resonance-stabilised β-ketoenolate binding pocket. We therefore synthesised a family of methylthio-functionalised DBM coordination compounds and subjected them, along with their truly aromatic terphenyl and 4,6-diphenylpyrimidine congeners, to scanning tunneling microscope break-junction (STM-BJ) experiments on gold nanoelectrodes. All molecules share the common motif of three π-conjugated, six-membered, planar rings with a meta-configuration at the central ring. According to our results, their molecular conductances fall within a factor of ca. 9 in an ordering aromatic < metallaaromatic < quasi-aromatic. The experimental trends are rationalised by quantum transport calculations based on density functional theory (DFT).
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Affiliation(s)
- André Mang
- Chemistry Department, University of Konstanz, 78457 Konstanz, Germany.
| | - Nils Rotthowe
- Chemistry Department, University of Konstanz, 78457 Konstanz, Germany.
| | - Katawoura Beltako
- Physics Department, University of Lomé, 1515 Lomé, Togo
- Institute of Physics, University of Augsburg, 86159 Augsburg, Germany.
| | - Michael Linseis
- Chemistry Department, University of Konstanz, 78457 Konstanz, Germany.
| | - Fabian Pauly
- Institute of Physics, University of Augsburg, 86159 Augsburg, Germany.
| | - Rainer F Winter
- Chemistry Department, University of Konstanz, 78457 Konstanz, Germany.
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15
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Mu Y, Yu J, Hu R, Wang CH, Cheng C, Hou BP. Ab initio study revealing remarkable oscillatory effects and negative differential resistance in the molecular device of silicon carbide chains. Phys Chem Chem Phys 2023; 25:13265-13274. [PMID: 36924456 DOI: 10.1039/d2cp05677a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
Inspired by the requirements of miniaturization and multifunction of molecular devices, we investigate the quantum transport properties of three unique molecular devices with silicon carbide chains bridging gold electrodes by an ab initio approach. The pronounced quantum effects, including the oscillation of charge, conductance, and current, together with the negative differential resistance (NDR), have been observed simultaneously over a wide region in the double-chain device. It changes the regular situation that these two effects usually emerge in single-chain systems at the same time. Inspections of the visible differences in the transport behaviors relevant to length and bias between the three devices further evidence that the interchain interaction and molecule-electrode coupling are decisive factors for achieving the quantum effects of oscillation and NDR. These two factors can improve electronic transport capability through enhancing transmission, strengthening the delocalization of frontier molecular orbitals, and reducing potential barriers. Our results not only lay a solid foundation for the application of silicon carbide chains in the miniaturized and multifunctional molecular devices with good performance, but also provide an efficient way to the continuing search for materials with multiple controllable quantum effects in nanoelectronics.
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Affiliation(s)
- Yi Mu
- College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu, China.
| | - Jie Yu
- College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu, China.
| | - Rui Hu
- College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu, China.
| | - Cui-Hong Wang
- College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu, China.
| | - Cai Cheng
- College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu, China.
| | - Bang-Pin Hou
- College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu, China.
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16
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Li L, Louie S, Evans AM, Meirzadeh E, Nuckolls C, Venkataraman L. Topological Radical Pairs Produce Ultrahigh Conductance in Long Molecular Wires. J Am Chem Soc 2023; 145:2492-2498. [PMID: 36689781 DOI: 10.1021/jacs.2c12059] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Molecular one-dimensional topological insulators (1D TIs), which conduct through energetically low-lying topological edge states, can be extremely highly conducting and exhibit a reversed conductance decay, affording them great potential as building blocks for nanoelectronic devices. However, these properties can only be observed at the short length limit. To extend the length at which these anomalous effects can be observed, we design topological oligo[n]emeraldine wires using short 1D TIs as building blocks. As the wire length increases, the number of topological states increases, enabling an increased electronic transmission along the wire; specifically, we show that we can drive over a microampere current through a single ∼5 nm molecular wire, appreciably more than what has been observed in other long wires reported to date. Calculations and experiments show that the longest oligo[7]emeraldine with doped topological states has over 106 enhancements in the transmission compared to its pristine form. The discovery of these highly conductive, long organic wires helps overcome a fundamental hurdle to implementing molecules in complex, nanoscale circuitry: their structures become too insulating at lengths that are useful in designing nanoscale circuits.
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Affiliation(s)
- Liang Li
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Shayan Louie
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Austin M Evans
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Elena Meirzadeh
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Latha Venkataraman
- Department of Chemistry, Columbia University, New York, New York10027, United States.,Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York10027, United States
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17
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Tang A, Li Y, Wang R, Yang J, Ma C, Li Z, Zou Q, Li H. Charge transport of F4TCNQ with different electronic states in single-molecule junctions. Chem Commun (Camb) 2023; 59:1305-1308. [PMID: 36633258 DOI: 10.1039/d2cc06341g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The molecular conductance of 2,3,5,6-tetrafluoro-7,7,8,8,-tetracyano-quinodimethane (F4TCNQ) with different electronic states (neutral, radical anion, and dianion) was investigated by the scanning tunneling microscope break junction (STM-BJ) technique. These electronic states have distinct conductance, and the conductance decreases in the order of neutral > radical anion > dianion. Surprisingly, the molecular conductance of the neutral F4TCNQ junction reaches 10-1.17G0, attributed to its LUMO energy level being close to the Fermi level of the gold electrode. Moreover, we found that neutral F4TCNQ can be gradually reduced to radical anions under a relatively low bias voltage of 100 mV. These results will advance the development of organic optoelectronic devices and molecule electronics.
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Affiliation(s)
- Ajun Tang
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China.
| | - Yunpeng Li
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China.
| | - Rui Wang
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China.
| | - Jiawei Yang
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China.
| | - Chaoqi Ma
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China.
| | - Zhi Li
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China.
| | - Qi Zou
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China.
| | - Hongxiang Li
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China.
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18
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Xu X, Wang J, Blankevoort N, Daaoub A, Sangtarash S, Shi J, Fang C, Yuan S, Chen L, Liu J, Yang Y, Sadeghi H, Hong W. Scaling of quantum interference from single molecules to molecular cages and their monolayers. Proc Natl Acad Sci U S A 2022; 119:e2211786119. [PMID: 36343232 PMCID: PMC9674264 DOI: 10.1073/pnas.2211786119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 10/11/2022] [Indexed: 11/09/2022] Open
Abstract
The discovery of quantum interference (QI) is widely considered as an important advance in molecular electronics since it provides unique opportunities for achieving single-molecule devices with unprecedented performance. Although some pioneering studies suggested the presence of spin qubit coherence and QI in collective systems such as thin films, it remains unclear whether the QI can be transferred step-by-step from single molecules to different length scales, which hinders the application of QI in fabricating active molecular devices. Here, we found that QI can be transferred from a single molecule to their assemblies. We synthesized and investigated the charge transport through the molecular cages using 1,3-dipyridylbenzene (DPB) as a ligand block with a destructive quantum interference (DQI) effect and 2,5-dipyridylfuran (DPF) as a control building block with a constructive quantum interference (CQI) effect using both single-molecule break junction and large area junction techniques. Combined experiments and calculations revealed that both DQI and CQI had been transferred from the ligand blocks to the molecular cages and the monolayer thin film of the cages. Our work introduced QI effects from a ligand to the molecular cage comprising 732 atoms and even their monolayers, suggesting that the quantum interference could be scaled up within the phase-coherent distance.
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Affiliation(s)
- Xiaohui Xu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University, Xiamen 361005, China
| | - Juejun Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University, Xiamen 361005, China
| | - Nickel Blankevoort
- Device Modelling Group, School of Engineering, University of Warwick, CV4 7AL Coventry, United Kingdom
| | - Abdalghani Daaoub
- Device Modelling Group, School of Engineering, University of Warwick, CV4 7AL Coventry, United Kingdom
| | - Sara Sangtarash
- Device Modelling Group, School of Engineering, University of Warwick, CV4 7AL Coventry, United Kingdom
| | - Jie Shi
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University, Xiamen 361005, China
| | - Chao Fang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University, Xiamen 361005, China
| | - Saisai Yuan
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University, Xiamen 361005, China
| | - Lichuan Chen
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University, Xiamen 361005, China
| | - Junyang Liu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University, Xiamen 361005, China
| | - Yang Yang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University, Xiamen 361005, China
| | - Hatef Sadeghi
- Device Modelling Group, School of Engineering, University of Warwick, CV4 7AL Coventry, United Kingdom
| | - Wenjing Hong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University, Xiamen 361005, China
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19
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Li L, Gunasekaran S, Wei Y, Nuckolls C, Venkataraman L. Reversed Conductance Decay of 1D Topological Insulators by Tight-Binding Analysis. J Phys Chem Lett 2022; 13:9703-9710. [PMID: 36219846 DOI: 10.1021/acs.jpclett.2c02812] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Reversed conductance decay describes increasing conductance of a molecular chain series with increasing chain length. Realizing reversed conductance decay is an important step toward making long and highly conducting molecular wires. Recent work has shown that one-dimensional topological insulators (1D TIs) can exhibit reversed conductance decay due to their nontrivial edge states. The Su-Schrieffer-Heeger (SSH) model for 1D TIs relates to the electronic structure of these isolated molecules but not their electron transport properties as single-molecule junctions. Herein, we use a tight-binding approach to demonstrate that polyacetylene and other diradicaloid 1D TIs show a reversed conductance decay at the short chain limit. We explain these conductance trends by analyzing the impact of the edge states in these 1D systems on the single-molecule junction transmission. Additionally, we discuss how the self-energy from the electrode-molecule coupling and the on-site energy of the edge sites can be tuned to create longer wires with reversed conductance decays.
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Affiliation(s)
- Liang Li
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Suman Gunasekaran
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York14853, United States
| | - Yujing Wei
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Latha Venkataraman
- Department of Chemistry, Columbia University, New York, New York10027, United States
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York10027, United States
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20
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Wang Z, Palma JL, Wang H, Liu J, Zhou G, Ajayakumar MR, Feng X, Wang W, Ulstrup J, Kornyshev AA, Li Y, Tao N. Electrochemically controlled rectification in symmetric single-molecule junctions. Proc Natl Acad Sci U S A 2022; 119:e2122183119. [PMID: 36136968 PMCID: PMC9522371 DOI: 10.1073/pnas.2122183119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Single-molecule electrochemical science has advanced over the past decades and now extends well beyond molecular imaging, to molecular electronics functions such as rectification and amplification. Rectification is conceptually the simplest but has involved mostly challenging chemical synthesis of asymmetric molecular structures or asymmetric materials and geometry of the two enclosing electrodes. Here we propose an experimental and theoretical strategy for building and tuning in situ (in operando) rectification in two symmetric molecular structures in electrochemical environment. The molecules were designed to conduct electronically via either their lowest unoccupied molecular orbital (LUMO; electron transfer) or highest occupied molecular orbital (HOMO; "hole transfer"). We used a bipotentiostat to control separately the electrochemical potential of the tip and substrate electrodes of an electrochemical scanning tunneling microscope (EC-STM), which leads to independent energy alignment of the STM tip, the molecule, and the STM substrate. By creating an asymmetric energy alignment, we observed single-molecule rectification of each molecule within a voltage range of ±0.5 V. By varying both the dominating charge transporting LUMO or HOMO energy and the electrolyte concentration, we achieved tuning of the polarity as well as the amplitude of the rectification. We have extended an earlier proposed theory that predicts electrolyte-controlled rectification to rationalize all the observed in situ rectification features and found excellent agreement between theory and experiments. Our study thus offers a way toward building controllable single-molecule rectifying devices without involving asymmetric molecular structures.
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Affiliation(s)
- Zixiao Wang
- aState Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
- 1To whom correspondence may be addressed. or or or
| | - Julio L. Palma
- bDepartment of Chemistry, Pennsylvania State University, Fayette, The Eberly Campus, Lemont Furnace, PA 15456
| | - Hui Wang
- aState Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Junzhi Liu
- cDepartment of Chemistry and State Key Laboratory of Synthetic Chemistry, the University of Hong Kong, Hong Kong, China
| | - Gang Zhou
- dLaboratory of Advanced Materials, State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai 200438, China
| | - M. R. Ajayakumar
- eCentre for Advancing Electronics Dresden, Faculty of Chemistry and Food Chemistry, Technische University Dresden, 01062 Dresden, Germany
| | - Xinliang Feng
- eCentre for Advancing Electronics Dresden, Faculty of Chemistry and Food Chemistry, Technische University Dresden, 01062 Dresden, Germany
| | - Wei Wang
- aState Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Jens Ulstrup
- fDepartment of Chemistry, Technical University of Denmark, Kongens Lyngby 2800, Denmark
- 1To whom correspondence may be addressed. or or or
| | - Alexei A. Kornyshev
- gDepartment of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, London W12 0BZ, United Kingdom
- 1To whom correspondence may be addressed. or or or
| | - Yueqi Li
- hCenter for Bioanalytical Chemistry, University of Science and Technology of China, Hefei 230026, China
- 1To whom correspondence may be addressed. or or or
| | - Nongjian Tao
- aState Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
- iCenter for Bioelectronics and Biosensors, Biodesign Institute and School of Electrical, Energy and Computer Engineering, Arizona State University, Tempe, AZ 85287
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21
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Dhindsa JS, Cotterill EL, Buguis FL, Anghel M, Boyle PD, Gilroy JB. Blending the Optical and Redox Properties of Oligoynes and Boron Difluoride Formazanates. Angew Chem Int Ed Engl 2022; 61:e202208502. [DOI: 10.1002/anie.202208502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Jasveer S. Dhindsa
- Department of Chemistry and the Centre for Advanced Materials and Biomaterials Research (CAMBR) The University of Western Ontario London ON N6A 5B7 Canada
| | - Erin L. Cotterill
- Department of Chemistry and the Centre for Advanced Materials and Biomaterials Research (CAMBR) The University of Western Ontario London ON N6A 5B7 Canada
| | - Francis L. Buguis
- Department of Chemistry and the Centre for Advanced Materials and Biomaterials Research (CAMBR) The University of Western Ontario London ON N6A 5B7 Canada
| | - Michael Anghel
- Department of Chemistry and the Centre for Advanced Materials and Biomaterials Research (CAMBR) The University of Western Ontario London ON N6A 5B7 Canada
| | - Paul D. Boyle
- Department of Chemistry and the Centre for Advanced Materials and Biomaterials Research (CAMBR) The University of Western Ontario London ON N6A 5B7 Canada
| | - Joe B. Gilroy
- Department of Chemistry and the Centre for Advanced Materials and Biomaterials Research (CAMBR) The University of Western Ontario London ON N6A 5B7 Canada
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22
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Gronowski M, Kołos R. A DFT Study on the Excited Electronic States of Cyanopolyynes: Benchmarks and Applications. Molecules 2022; 27:molecules27185829. [PMID: 36144567 PMCID: PMC9500640 DOI: 10.3390/molecules27185829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/16/2022] Open
Abstract
Highly unsaturated chain molecules are interesting due to their potential application as nanowires and occurrence in interstellar space. Here, we focus on predicting the electronic spectra of polyynic nitriles HC2m+1N (m = 0–13) and dinitriles NC2n+2N (n = 0–14). The results of time-dependent density functional theory (TD-DFT) calculations are compared with the available gas-phase and noble gas matrix experimental data. We assessed the performance of fifteen functionals and five basis sets for reproducing (i) vibrationless electronic excitation energies and (ii) vibrational frequencies in the singlet excited states. We found that the basis sets of at least triple-ζ quality were necessary to describe the long molecules with alternate single and triple bonds. Vibrational frequency scaling factors are similar for the ground and excited states. The benchmarked spectroscopic parameters were shown to be acceptably reproduced with adequately chosen functionals, in particular ωB97X, CAM-B3LYP, B3LYP, B971, and B972. Select functionals were applied to study the electronic excitation of molecules up to HC27N and C30N2. It is demonstrated that optical excitation leads to a shift from the polyyne- to a cumulene-like electronic structure.
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23
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Feng A, Hou S, Yan J, Wu Q, Tang Y, Yang Y, Shi J, Xiao ZY, Lambert CJ, Zheng N, Hong W. Conductance Growth of Single-Cluster Junctions with Increasing Sizes. J Am Chem Soc 2022; 144:15680-15688. [PMID: 35984293 DOI: 10.1021/jacs.2c05856] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quantum-tunneling-based nanoelectronics has the potential for the miniaturization of electronics toward the sub-5 nm scale. However, the nature of phase-coherent quantum tunneling leads to the rapid decays of the electrical conductance with tunneling transport distance, especially in organic molecule-based nanodevices. In this work, we investigated the conductance of the single-cluster junctions of a series of atomically well-defined silver nanoclusters, with varying sizes from 0.9 to 3.0 nm, using the mechanically controllable break junction (MCBJ) technique combined with quantum transport theory. Our charge transport investigations of these single-cluster junctions revealed that the conductance grows with increasing cluster size. The conductance decay constant was determined to be ∼-0.4 nm-1, which is of opposite sign to that of organic molecules. Comparison between experiment and theory reveals that although charge transport through the silver single-cluster junctions occurs via phase-coherent tunneling, this is compensated by a rapid decrease in the energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO-LUMO gap) with size and the increase in the electrode-cluster coupling, which results in their conductance increase up to lengths of ∼3.0 nm. These results demonstrate that such families of nanoclusters provide unique bottom-up building blocks for the fabrication of nanodevices in the sub-5 nm size range.
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Affiliation(s)
- Anni Feng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, 361005 Xiamen, China
| | - Songjun Hou
- Department of Physics, Lancaster University, Lancaster LA1 4YB, United Kingdom
| | - Juanzhu Yan
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, 361005 Xiamen, China
| | - Qingqing Wu
- Department of Physics, Lancaster University, Lancaster LA1 4YB, United Kingdom
| | - Yongxiang Tang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, 361005 Xiamen, China
| | - Yang Yang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, 361005 Xiamen, China
| | - Jia Shi
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, 361005 Xiamen, China
| | - Zong-Yuan Xiao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, 361005 Xiamen, China
| | - Colin J Lambert
- Department of Physics, Lancaster University, Lancaster LA1 4YB, United Kingdom
| | - Nanfeng Zheng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, 361005 Xiamen, China
| | - Wenjing Hong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, 361005 Xiamen, China
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24
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Dhindsa JS, Cotterrill EL, Buguis FL, Anghel M, Boyle PD, Gilroy JB. Blending the Optical and Redox Properties of Oligoynes and Boron. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202208502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jasveer S Dhindsa
- University of Western Ontario: Western University Department of Chemistry CANADA
| | - Erin L. Cotterrill
- University of Western Ontario: Western University Department of Chemistry CANADA
| | - Francis L. Buguis
- University of Western Ontario: Western University Department of Chemistry CANADA
| | - Michael Anghel
- University of Western Ontario: Western University Department of Chemistry CANADA
| | - Paul D. Boyle
- University of Western Ontario: Western University Department of Chemistry CANADA
| | - Joe B. Gilroy
- The University of Western Ontario Department of Chemistry 1151 Richmond St. N. N6A 5B7 London CANADA
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25
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Li L, Low JZ, Wilhelm J, Liao G, Gunasekaran S, Prindle CR, Starr RL, Golze D, Nuckolls C, Steigerwald ML, Evers F, Campos LM, Yin X, Venkataraman L. Highly conducting single-molecule topological insulators based on mono- and di-radical cations. Nat Chem 2022; 14:1061-1067. [PMID: 35798950 DOI: 10.1038/s41557-022-00978-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 05/18/2022] [Indexed: 11/09/2022]
Abstract
Single-molecule topological insulators are promising candidates as conducting wires over nanometre length scales. A key advantage is their ability to exhibit quasi-metallic transport, in contrast to conjugated molecular wires which typically exhibit a low conductance that decays as the wire length increases. Here, we study a family of oligophenylene-bridged bis(triarylamines) with tunable and stable mono- or di-radicaloid character. These wires can undergo one- and two-electron chemical oxidations to the corresponding mono-cation and di-cation, respectively. We show that the oxidized wires exhibit reversed conductance decay with increasing length, consistent with the expectation for Su-Schrieffer-Heeger-type one-dimensional topological insulators. The 2.6-nm-long di-cation reported here displays a conductance greater than 0.1G0, where G0 is the conductance quantum, a factor of 5,400 greater than the neutral form. The observed conductance-length relationship is similar between the mono-cation and di-cation series. Density functional theory calculations elucidate how the frontier orbitals and delocalization of radicals facilitate the observed non-classical quasi-metallic behaviour.
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Affiliation(s)
- Liang Li
- Department of Chemistry, Columbia University, New York, NY, USA
| | - Jonathan Z Low
- Department of Chemistry, Columbia University, New York, NY, USA
| | - Jan Wilhelm
- Institute of Theoretical Physics, University of Regensburg, Regensburg, Germany
| | - Guanming Liao
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, P. R. China
| | | | | | - Rachel L Starr
- Department of Chemistry, Columbia University, New York, NY, USA
| | - Dorothea Golze
- Technische Universität Dresden, Dresden, König-Bau, Germany
| | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York, NY, USA
| | | | - Ferdinand Evers
- Institute of Theoretical Physics, University of Regensburg, Regensburg, Germany.
| | - Luis M Campos
- Department of Chemistry, Columbia University, New York, NY, USA.
| | - Xiaodong Yin
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, P. R. China.
| | - Latha Venkataraman
- Department of Chemistry, Columbia University, New York, NY, USA. .,Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY, USA.
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26
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Zou Q, Chen X, Zhou Y, Jin X, Zhang Z, Qiu J, Wang R, Hong W, Su J, Qu DH, Tian H. Photoconductance from the Bent-to-Planar Photocycle between Ground and Excited States in Single-Molecule Junctions. J Am Chem Soc 2022; 144:10042-10052. [PMID: 35611861 DOI: 10.1021/jacs.2c03671] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Single-molecule conductance measurements for 9,14-diphenyl-9,14-dihydrodibenzo[a,c]phenazine (DPAC) may offer unique insight into the bent-to-planar photocycle between the ground and excited states. Herein, we employ DPAC derivative DPAC-SMe as the molecular prototype to fabricate single-molecule junctions using the scanning tunneling microscope break junction technique and explore photoconductance dependence on the excited-state structural/electronic changes. We find up to ∼200% conductance enhancement of DPAC-SMe under continuous 340 nm light irradiation than that without irradiation, while photoconductance disappears in the case where structural evolution of the DPAC-SMe is halted through macrocyclization. The in situ conductance modulation as pulsed 340 nm light irradiation is monitored in the DPAC-SMe-based junctions alone, suggesting that the photoconductance of DPAC-SMe stems from photoinduced intramolecular planarization. Theoretical calculations reveal that the photoinduced structural evolution brings about a significant redistribution of the electron cloud density, which leads to the appearance of Fano resonance, resulting in enhanced conductance through the DPAC-SMe-fabricated junctions. This work provides evidence of bent-to-planar photocycle-induced conductance differences at the single-molecule level, offering a tailored approach for tuning the charge transport characteristics of organic photoelectronic devices.
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Affiliation(s)
- Qi Zou
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Xuanying Chen
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yu Zhou
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xin Jin
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Zhiyun Zhang
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Jin Qiu
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Rui Wang
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Wenjing Hong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jianhua Su
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Da-Hui Qu
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - He Tian
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
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27
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Pecorario S, Scaccabarozzi AD, Fazzi D, Gutiérrez-Fernández E, Vurro V, Maserati L, Jiang M, Losi T, Sun B, Tykwinski RR, Casari CS, Caironi M. Stable and Solution-Processable Cumulenic sp-Carbon Wires: A New Paradigm for Organic Electronics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2110468. [PMID: 35178779 DOI: 10.1002/adma.202110468] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/07/2022] [Indexed: 06/14/2023]
Abstract
Solution-processed, large-area, and flexible electronics largely relies on the excellent electronic properties of sp2 -hybridized carbon molecules, either in the form of π-conjugated small molecules and polymers or graphene and carbon nanotubes. Carbon with sp-hybridization, the foundation of the elusive allotrope carbyne, offers vast opportunities for functionalized molecules in the form of linear carbon atomic wires (CAWs), with intriguing and even superior predicted electronic properties. While CAWs represent a vibrant field of research, to date, they have only been applied sparingly to molecular devices. The recent observation of the field-effect in microcrystalline cumulenes suggests their potential applications in solution-processed thin-film transistors but concerns surrounding the stability and electronic performance have precluded developments in this direction. In the present study, ideal field-effect characteristics are demonstrated for solution-processed thin films of tetraphenyl[3]cumulene, the shortest semiconducting CAW. Films are deposited through a scalable, large-area, meniscus-coating technique, providing transistors with hole mobilities in excess of 0.1 cm2 V-1 s-1 , as well as promising operational stability under dark conditions. These results offer a solid foundation for the exploitation of a vast class of molecular semiconductors for organic electronics based on sp-hybridized carbon systems and create a previously unexplored paradigm.
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Affiliation(s)
- Stefano Pecorario
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
- Department of Energy, Micro and Nanostructured Materials Laboratory - NanoLab, Politecnico di Milano, Via Ponzio 34/3, Milano, 20133, Italy
| | - Alberto D Scaccabarozzi
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Daniele Fazzi
- Department of Chemistry "Giacomo Ciamician", Università di Bologna, Via F. Selmi, 2, Bologna, 40126, Italy
| | | | - Vito Vurro
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Lorenzo Maserati
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Mengting Jiang
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Tommaso Losi
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Bozheng Sun
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - Rik R Tykwinski
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - Carlo S Casari
- Department of Energy, Micro and Nanostructured Materials Laboratory - NanoLab, Politecnico di Milano, Via Ponzio 34/3, Milano, 20133, Italy
| | - Mario Caironi
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
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28
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Johnson MA, Martin M, Cocq K, Ferguson M, Jux N, Tykwinski RR. Acylation of Hexaphenylbenzene for the Synthesis of [5]Cumulenes. European J Org Chem 2022. [DOI: 10.1002/ejoc.202101467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Max Martin
- FAU Erlangen Nuremberg: Friedrich-Alexander-Universitat Erlangen-Nurnberg Chemistry GERMANY
| | - Kévin Cocq
- University of Alberta Department of Chemistry CANADA
| | | | - Norbert Jux
- FAU: Friedrich-Alexander-Universitat Erlangen-Nurnberg Chemistry GERMANY
| | - Rik R. Tykwinski
- University of Alberta Department of Chemistry T6G 2G2 Edmonton CANADA
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29
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Balakrishnan A, Vijayakumar S. Highly delocalised molecular orbitals in boron-, carbon- and nitrogen-based linear chains: a DFT study. Mol Phys 2022. [DOI: 10.1080/00268976.2021.2020923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - S. Vijayakumar
- Department of Medical Physics, Bharathiar University, Coimbatore, India
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30
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Kaur P, Ali ME. Influence of the Radicaloid Character of Polyaromatic Hydrocarbon Couplers on Magnetic Exchange Interactions. Phys Chem Chem Phys 2022; 24:13094-13101. [DOI: 10.1039/d1cp02044g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The molecular properties of the conjugated spacers, such as the π-conjugation, aromaticity, length of the couplers, etc., that couple two localized spin-centers influence the intramolecular magnetic exchange interactions (2J) mediated...
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31
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Geometrical, electrical, and energetic parameters of hetero-disubstituted cumulenes and polyynes in the presence and absence of the external electric field. Struct Chem 2021. [DOI: 10.1007/s11224-021-01858-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
AbstractCumulenes and polyynes have the potential to be applied as linear, sp-hybridized, one-dimensional all-carbon nanowires in molecular electronics and optoelectronics. The delocalization and conductivity descriptors of the two π-conjugated systems, heterodisubstituted with the NO2, CN, NH2, and OH groups, were studied using the B3LYP, B3LYP/D3, CAM-B3LYP, and ωB97XD DFT functionals, combined with the aug-cc-pVTZ basis set. Three independent types of molecular descriptors, based on geometry (the HOMA index), electrical properties (trace of the polarizability tensor), and energetic (the HOMO-LUMO energy gap) were shown to be mutually correlated and provided concordant indication that communication through the cumulene chain was considerably better than through the polyyne one. The communication can be tuned by using substituents of significantly different π-electron donor-acceptor properties as well as by the external electric field directed along the carbon chain.
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32
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Xu W, Leary E, Sangtarash S, Jirasek M, González MT, Christensen KE, Abellán Vicente L, Agraït N, Higgins SJ, Nichols RJ, Lambert CJ, Anderson HL. A Peierls Transition in Long Polymethine Molecular Wires: Evolution of Molecular Geometry and Single-Molecule Conductance. J Am Chem Soc 2021; 143:20472-20481. [PMID: 34817985 DOI: 10.1021/jacs.1c10747] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Molecules capable of mediating charge transport over several nanometers with minimal decay in conductance have fundamental and technological implications. Polymethine cyanine dyes are fascinating molecular wires because up to a critical length, they have no bond-length alternation (BLA) and their electronic structure resembles a one-dimensional free-electron gas. Beyond this threshold, they undergo a symmetry-breaking Peierls transition, which increases the HOMO-LUMO gap. We have investigated cationic cyanines with central polymethine chains of 5-13 carbon atoms (Cy3+-Cy11+). The absorption spectra and crystal structures show that symmetry breaking is sensitive to the polarity of the medium and the size of the counterion. X-ray crystallography reveals that Cy9·PF6 and Cy11·B(C6F5)4 are Peierls distorted, with high BLA at one end of the π-system, away from the partially delocalized positive charge. This pattern of BLA distribution resembles that of solitons in polyacetylene. The single-molecule conductance is essentially independent of molecular length for the polymethine salts of Cy3+-Cy11+ with the large B(C6F5)4- counterion, but with the PF6- counterion, the conductance decreases for the longer molecules, Cy7+-Cy11+, because this smaller anion polarizes the π-system, inducing a symmetry-breaking transition. At higher bias (0.9 V), the conductance of the shorter chains, Cy3+-Cy7+, increases with length (negative attenuation factor, β = -1.6 nm-1), but the conductance still drops in Cy9+ and Cy11+ with the small polarizing PF6- counteranion.
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Affiliation(s)
- Wenjun Xu
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Edmund Leary
- Fundación IMDEA Nanociencia, Calle Faraday 9, Campus Universitario de Cantoblanco, 28049 Madrid, Spain
| | - Sara Sangtarash
- School of Engineering, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Michael Jirasek
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - M Teresa González
- Fundación IMDEA Nanociencia, Calle Faraday 9, Campus Universitario de Cantoblanco, 28049 Madrid, Spain
| | - Kirsten E Christensen
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Lydia Abellán Vicente
- Fundación IMDEA Nanociencia, Calle Faraday 9, Campus Universitario de Cantoblanco, 28049 Madrid, Spain
| | - Nicolás Agraït
- Fundación IMDEA Nanociencia, Calle Faraday 9, Campus Universitario de Cantoblanco, 28049 Madrid, Spain.,Departamento de Física de la Materia Condensada, IFIMAC and Instituto "Nicolás Cabrera", Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Simon J Higgins
- Department of Chemistry, Donnan and Robert Robinson Laboratories, University of Liverpool, Liverpool L69 7ZD, United Kingdom
| | - Richard J Nichols
- Department of Chemistry, Donnan and Robert Robinson Laboratories, University of Liverpool, Liverpool L69 7ZD, United Kingdom
| | - Colin J Lambert
- Department of Physics, Lancaster University, Lancaster LA1 4YW, United Kingdom
| | - Harry L Anderson
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
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33
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Hall MR, Moggach SA, Low PJ. Syntheses and Structures of trans-bis(Alkenylacetylide) Ruthenium Complexes. Chem Asian J 2021; 16:3385-3403. [PMID: 34468081 DOI: 10.1002/asia.202100850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 08/25/2021] [Indexed: 11/08/2022]
Abstract
A series of ruthenium alkenylacetylide complexes trans-[Ru{C≡CC(=CH2 )R}Cl(dppe)2 ] (R=Ph (1 a), c C4 H3 S (1 b), 4-MeS-C6 H4 (1 c), 3,3-dimethyl-2,3-dihydrobenzo[b]thiophene (DMBT) (1 d)) or trans-[Ru{C≡C-c C6 H9 }Cl(dppe)2 ] (1 e) were allowed to react with the corresponding propargylic alcohol HC≡CC(Me)R(OH) (R=Ph (A), c C4 H3 S (B), 4-MeS-C6 H4 (C), DMBT (D) or HC≡C-c C6 H10 (OH) (E) in the presence of TlBF4 and DBU to presumably give alkenylacetylide/allenylidene intermediates trans-[Ru{C≡CC(=CH2 )R}{C=C=C(Me)}(dppe)2 ]PF6 ([2]PF6 ). These complexes were not isolated but deprotonated to give the isolable bis(alkenylacetylide) complexes trans-[Ru{C≡CC(=CH2 )R}2 (dppe)2 ] (R=Ph (3 a), c C4 H3 S (3 b), 4-MeS-C6 H4 (3 c), DMBT (3 d)) and trans-[Ru{C≡C-c C6 H9 }2 (dppe)2 ] (3 e). Analogous reactions of trans-[Ru(CH3 )2 (dmpe)2 ], featuring the more electron-donating 1,2-bis(dimethylphosphino)ethane (dmpe) ancillary ligands, with the propargylic alcohols A or C and NH4 PF6 in methanol allowed isolation of the intermediate mixed alkenylacetylide/allenylidene complexes trans-[Ru{C≡CC(=CH2 )R}{C=C=C(Me)}(dmpe)2 ]PF6 (R=Ph ([4 a]PF6 ), 4-MeS-C6 H4 ([4 c]PF6 ). Deprotonation of [4 a]PF6 or [4 c]PF6 gave the symmetric bis(alkenylacetylide) complexes trans-[Ru{C≡CC(=CH2 )R}2 (dmpe)2 ] (R=Ph (5 a), 4-MeS-C6 H4 (5 c)), the first of their kind containing the dmpe ancillary ligand sphere. Attempts to isolate bis(allenylidene) complexes [Ru{C=C=C(Me)R}2 (PP)2 ]2+ (PP=dppe, dmpe) from treatment of the bis(alkenylacetylide) species 3 or 5 with HBF4 ⋅ Et2 O were ultimately unsuccessful.
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Affiliation(s)
- Michael R Hall
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia, Australia
| | - Stephen A Moggach
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia, Australia
| | - Paul J Low
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia, Australia
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34
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Jiang W, Tan Z, Almughathawi R, Wu Q, Liu Z, Liu J, Hou S, Zhang G, Lambert CJ, Hong W, Zhang D. Single-Molecule Charge-Transport Modulation Induced by Steric Effects of Side Alkyl Chains. Chemphyschem 2021; 22:2573-2578. [PMID: 34636146 DOI: 10.1002/cphc.202100634] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/09/2021] [Indexed: 11/08/2022]
Abstract
The experimental investigation of side-chain effects on intramolecular charge transport in π-conjugated molecules is essential but remains challenging. Herein, the dependence of intra-molecular conductance on the nature of branching alkyl chains is investigated through a combination of the scanning tunneling microscope break junction (STM-BJ) technique and density functional theory. Three thiophene-flanked diketopyrrolopyrrole (DPP) derivatives with different branching alkyl chains (isopentane, 3-methylheptane, and 9-methylnonadecane) are used with phenylthiomethyl groups as the anchoring groups. The results of single-molecule conductance measurements show that as the alkyl chain becomes longer, the torsional angles between the aromatic rings increase due to steric crowding, and therefore, the molecular conductance of DPP decreases due to reduction in conjugation. Both theoretical simulations and 1 H NMR spectra demonstrate that the planarity of the DPPs is directly reduced after introducing longer branching alkyl chains, which leads to a reduced conductance. This work indicates that the effect of the insulating side chain on the single-molecule conductance cannot be neglected, which should be considered for the design of future organic semiconducting materials.
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Affiliation(s)
- Wenlin Jiang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory for Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Zhibing Tan
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Siming South Road, China
| | | | - Qingqing Wu
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - Zitong Liu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory for Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Junyang Liu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Siming South Road, China
| | - Songjun Hou
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - Guanxin Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory for Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Colin J Lambert
- Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK
| | - Wenjing Hong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Siming South Road, China
| | - Deqing Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory for Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
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35
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O'Driscoll LJ, Bryce MR. A review of oligo(arylene ethynylene) derivatives in molecular junctions. NANOSCALE 2021; 13:10668-10711. [PMID: 34110337 DOI: 10.1039/d1nr02023d] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Oligo(arylene ethynylene) (OAE) derivatives are the "workhorse" molecules of molecular electronics. Their ease of synthesis and flexibility of functionalisation mean that a diverse array of OAE molecular wires have been designed, synthesised and studied theoretically and experimentally in molecular junctions using both single-molecule and ensemble methods. This review summarises the breadth of molecular designs that have been investigated with emphasis on structure-property relationships with respect to the electronic conductance of OAEs. The factors considered include molecular length, connectivity, conjugation, (anti)aromaticity, heteroatom effects and quantum interference (QI). Growing interest in the thermoelectric properties of OAE derivatives, which are expected to be at the forefront of research into organic thermoelectric devices, is also explored.
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Affiliation(s)
- Luke J O'Driscoll
- Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham, UKDH1 3LE.
| | - Martin R Bryce
- Department of Chemistry, Durham University, Lower Mountjoy, Stockton Road, Durham, UKDH1 3LE.
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36
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Ramos-Berdullas N, Gil-Guerrero S, Peña-Gallego Á, Mandado M. The effect of spin polarization on the electron transport of molecular wires with diradical character. Phys Chem Chem Phys 2021; 23:4777-4783. [PMID: 33599227 DOI: 10.1039/d0cp06321e] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Some of the most promising materials for application in molecular electronics and spintronics are based on diradical chains. Herein, the proposed relation between increasing conductance with length and diradical character is revisited using ab initio methods that account for the static electron correlation effects. Electron transmission was previously obtained from restricted single determinant wavefuntions or tight-binding approximations, which are unable to account for static correlation. Broken Symmetry Unrestricted Kohn-Sham Density Functional Theory (BS-UKS-DFT) in combination with electron transport analysis based on electron deformation orbitals (EDOs) reflects an exponential decay of the electrical conductance with length. Also, other important effects such as quantum interference are correctly accounted for, leading to a decrease of the conductance as the diradical character increases. As a proof-of-concept, the electrical conductance obtained from BS-UKS-DFT and CASSCF(2,2) wavefunctions were compared in diradical graphene strips in the frame of the pseudo-π approach, obtaining very similar results.
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Affiliation(s)
- Nicolás Ramos-Berdullas
- Department of Physical Chemistry, University of Vigo, Lagoas-Marcosende s/n, 36310, Vigo, Spain.
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