1
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Li H, Felix LC, Li Q, Ruan Q, Yakobson BI, Hersam MC. Atomic-Resolution Vibrational Mapping of Bilayer Borophene. NANO LETTERS 2024; 24:10674-10680. [PMID: 39141815 DOI: 10.1021/acs.nanolett.4c03224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/16/2024]
Abstract
The successful synthesis of borophene beyond the monolayer limit has expanded the family of two-dimensional boron nanomaterials. While atomic-resolution topographic imaging has been previously reported, vibrational mapping has the potential to reveal deeper insight into the chemical bonding and electronic properties of bilayer borophene. Herein, inelastic electron tunneling spectroscopy (IETS) is used to resolve the low-energy vibrational and electronic properties of bilayer-α (BL-α) borophene on Ag(111) at the atomic scale. Using a carbon monoxide (CO)-functionalized scanning tunneling microscopy tip, the BL-α borophene IETS spectra reveal unique features compared to single-layer borophene and typical CO vibrations on metal surfaces. Distinct vibrational spectra are further observed for hollow and filled boron hexagons within the BL-α borophene unit cell, providing evidence for interlayer bonding between the constituent borophene layers. These experimental results are compared with density functional theory calculations to elucidate the interplay between the vibrational modes and electronic states in bilayer borophene.
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Affiliation(s)
- Hui Li
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Levi C Felix
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
| | - Qiucheng Li
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Qiyuan Ruan
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
| | - Boris I Yakobson
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 75005, United States
| | - Mark C Hersam
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- Department of Electrical and Computer Engineering, Northwestern University, Evanston, Illinois 60208, United States
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2
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Alkorta M, Cizek R, Néel N, Frederiksen T, Kröger J. Impact of Single-Melamine Tautomerization on the Excitation of Molecular Vibrations in Inelastic Electron Tunneling Spectroscopy. NANO LETTERS 2024; 24:7195-7201. [PMID: 38748446 PMCID: PMC11194823 DOI: 10.1021/acs.nanolett.4c00904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 05/10/2024] [Accepted: 05/10/2024] [Indexed: 06/26/2024]
Abstract
Vibrational quanta of melamine and its tautomer are analyzed at the single-molecule level on Cu(100) with inelastic electron tunneling spectroscopy. The on-surface tautomerization gives rise to markedly different low-energy vibrational spectra of the isomers, as evidenced by a shift in mode energies and a variation in inelastic cross sections. Spatially resolved spectroscopy reveals the maximum signal strength on an orbital nodal plane, excluding resonant inelastic tunneling as the mechanism underlying the quantum excitations. Decreasing the probe-molecule separation down to the formation of a chemical bond between the melamine amino group and the Cu apex atom of the tip leads to a quenched vibrational spectrum with different excitation energies. Density functional and electron transport calculations reproduce the experimental findings and show that the shift in the quantum energies applies to internal molecular bending modes. The simulations moreover suggest that the bond formation represents an efficient manner of tautomerizing the molecule.
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Affiliation(s)
- Manex Alkorta
- Donostia
International Physics Center (DIPC), E-20018 Donostia-San Sebastián, Spain
- Centro
de Física de Materiales (CFM) CSIC-UPV/EHU, E-20018 Donostia-San Sebastián, Spain
| | - Rebecca Cizek
- Institut
für Physik, Technische Universität
Ilmenau, D-98693 Ilmenau, Germany
| | - Nicolas Néel
- Institut
für Physik, Technische Universität
Ilmenau, D-98693 Ilmenau, Germany
| | - Thomas Frederiksen
- Donostia
International Physics Center (DIPC), E-20018 Donostia-San Sebastián, Spain
- IKERBASQUE,
Basque Foundation for Science, E-48011 Bilbao, Spain
| | - Jörg Kröger
- Institut
für Physik, Technische Universität
Ilmenau, D-98693 Ilmenau, Germany
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3
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Kurki L, Oinonen N, Foster AS. Automated Structure Discovery for Scanning Tunneling Microscopy. ACS NANO 2024; 18:11130-11138. [PMID: 38644571 PMCID: PMC11064214 DOI: 10.1021/acsnano.3c12654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/25/2024] [Accepted: 04/05/2024] [Indexed: 04/23/2024]
Abstract
Scanning tunneling microscopy (STM) with a functionalized tip apex reveals the geometric and electronic structures of a sample within the same experiment. However, the complex nature of the signal makes images difficult to interpret and has so far limited most research to planar samples with a known chemical composition. Here, we present automated structure discovery for STM (ASD-STM), a machine learning tool for predicting the atomic structure directly from an STM image, by building upon successful methods for structure discovery in noncontact atomic force microscopy (nc-AFM). We apply the method on various organic molecules and achieve good accuracy on structure predictions and chemical identification on a qualitative level while highlighting future development requirements for ASD-STM. This method is directly applicable to experimental STM images of organic molecules, making structure discovery available for a wider scanning probe microscopy audience outside of nc-AFM. This work also allows more advanced machine learning methods to be developed for STM structure discovery.
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Affiliation(s)
- Lauri Kurki
- Department
of Applied Physics, Aalto University, Aalto, Espoo 00076, Finland
| | - Niko Oinonen
- Department
of Applied Physics, Aalto University, Aalto, Espoo 00076, Finland
- Nanolayers
Research Computing Ltd., London N12 0HL, U.K.
| | - Adam S. Foster
- Department
of Applied Physics, Aalto University, Aalto, Espoo 00076, Finland
- WPI
Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
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4
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Zhang BQ, Ma FC, Xu JN, Ren DD, Zhou D, Pan T, Zhou L, Pu Q, Zeng ZC. Calibration of the oscillation amplitude of quartz tuning fork-based force sensors with astigmatic displacement microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:015007. [PMID: 38284812 DOI: 10.1063/5.0183470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 01/03/2024] [Indexed: 01/30/2024]
Abstract
Quartz tuning forks and qPlus-based force sensors offer an alternative approach to silicon cantilevers for investigating tip-sample interactions in scanning probe microscopy. The high-quality factor (Q) and stiffness of these sensors prevent the tip from jumping to the contact, even at sub-nanometer amplitude. The qPlus configuration enables simultaneous scanning tunneling microscopy and atomic force microscopy, achieving spatial resolution and spectroscopy at the subatomic level. However, to enable precise measurement of tip-sample interaction forces, confidence in these measurements is contingent upon the accurate calibration of the spring constant and oscillation amplitude of the sensor. Here, we have developed a method called astigmatic displacement microscopy with picometer sensitivity.
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Affiliation(s)
- Bi-Qin Zhang
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Fei-Cen Ma
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Jia-Nan Xu
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Dou-Dou Ren
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Dan Zhou
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Ting Pan
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Lei Zhou
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Qiaosheng Pu
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Zhi-Cong Zeng
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China
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5
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Zhang H, Lu J, Zhao XJ, Li B, Zhou H, Zhang Y, Niu G, Fu B, Gao L, Tan YZ, Cai J. Length-Dependent Magnetic Evolution of Anthenes on Au(111). Angew Chem Int Ed Engl 2023; 62:e202315216. [PMID: 37933811 DOI: 10.1002/anie.202315216] [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: 10/09/2023] [Revised: 11/06/2023] [Accepted: 11/07/2023] [Indexed: 11/08/2023]
Abstract
Nanographenes with zigzag edges, for example, anthenes, exhibit a unique nonbonding π-electron state, which can be described as a spin-polarized edge state that yields specific magnetic ground state. However, prior researches on the magnetism of anthenes with varying lengths on a surface is lacking. This study systematically fabricated anthenes with inherent zigzag carbon atoms of different lengths ranging from bisanthene to hexanthene. Their magnetic evolution on the Au(111) surface was analyzed through bond-resolved scanning probe techniques and density functional theory calculations. The analyses revealed a transition in magnetic properties associated with the length of the anthenes, arising from the imbalance between hybridization energy and the Coulomb repulsion between valence electrons. With the increasing length of the anthenes, the ground state transforms gradually from a closed-shell to an antiferromagnetic open-shell singlet, exhibiting a weak exchange coupling of 4 meV and a charge transfer-induced doublet. Therefore, this study formulated a chemically tunable platform to explore size-dependent π magnetism at the atomic scale, providing a framework for research in organic spintronics.
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Affiliation(s)
- Hui Zhang
- Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China
| | - Jianchen Lu
- Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China
| | - Xin-Jing Zhao
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Baijin Li
- Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China
| | - Hangjing Zhou
- Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China
| | - Yong Zhang
- Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China
| | - Gefei Niu
- Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China
| | - Boyu Fu
- Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China
| | - Lei Gao
- Faculty of Science, Kunming University of Science and Technology, Kunming, 650500, China
| | - Yuan-Zhi Tan
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Jinming Cai
- Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China
- Southwest United Graduate School, Kunming, 650093, China
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6
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Vilas-Varela M, Romero-Lara F, Vegliante A, Calupitan JP, Martínez A, Meyer L, Uriarte-Amiano U, Friedrich N, Wang D, Schulz F, Koval NE, Sandoval-Salinas ME, Casanova D, Corso M, Artacho E, Peña D, Pascual JI. On-Surface Synthesis and Characterization of a High-Spin Aza-[5]-Triangulene. Angew Chem Int Ed Engl 2023; 62:e202307884. [PMID: 37604782 DOI: 10.1002/anie.202307884] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 08/11/2023] [Accepted: 08/17/2023] [Indexed: 08/23/2023]
Abstract
Triangulenes are a class of open-shell triangular graphene flakes with total spin increasing with their size. In the last years, on-surface-synthesis strategies have permitted fabricating and engineering triangulenes of various sizes and structures with atomic precision. However, direct proof of the increasing total spin with their size remains elusive. In this work, we report the combined in-solution and on-surface synthesis of a large nitrogen-doped triangulene (aza-[5]-triangulene) on a Au(111) surface, and the detection of its high-spin ground state. Bond-resolved scanning tunneling microscopy images uncovered radical states distributed along the zigzag edges, which were detected as weak zero-bias resonances in scanning tunneling spectra. These spectral features reveal the partial Kondo screening of a high-spin state. Through a combination of several simulation tools, we find that the observed distribution of radical states is explained by a quintet ground state (S=2), instead of the quartet state (S=3/2) expected for the neutral species. This confirms that electron transfer to the metal substrate raises the spin of the ground state. We further provide a qualitative description of the change of (anti)aromaticity introduced by N-substitution, and its role in the charge stabilization on a surface, resulting in an S=2 aza-triangulene on Au(111).
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Affiliation(s)
- Manuel Vilas-Varela
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782-, Santiago de Compostela, Spain
| | | | | | - Jan Patrick Calupitan
- Centro de Física de Materiales CSIC/UPV-EHU-Materials Physics Center, 20018, Donostia-San Sebastián, Spain
- Donostia International Physics Center (DIPC), 20018, Donostia-San Sebastián, Spain
| | - Adrián Martínez
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782-, Santiago de Compostela, Spain
| | - Lorenz Meyer
- CIC nanoGUNE-BRTA, 20018, Donostia-San Sebastián, Spain
| | | | | | - Dongfei Wang
- CIC nanoGUNE-BRTA, 20018, Donostia-San Sebastián, Spain
| | - Fabian Schulz
- CIC nanoGUNE-BRTA, 20018, Donostia-San Sebastián, Spain
| | | | | | - David Casanova
- Donostia International Physics Center (DIPC), 20018, Donostia-San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48009, Bilbao, Spain
| | - Martina Corso
- Centro de Física de Materiales CSIC/UPV-EHU-Materials Physics Center, 20018, Donostia-San Sebastián, Spain
| | - Emilio Artacho
- CIC nanoGUNE-BRTA, 20018, Donostia-San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48009, Bilbao, Spain
- Theory of Condensed Matter, Cavendish Laboratory, University of Cambridge, J. J. Thomson Ave., Cambridge, CB3 0HE, UK
| | - Diego Peña
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782-, Santiago de Compostela, Spain
| | - José Ignacio Pascual
- CIC nanoGUNE-BRTA, 20018, Donostia-San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48009, Bilbao, Spain
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7
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Real-space imaging of a phenyl group migration reaction on metal surfaces. Nat Commun 2023; 14:970. [PMID: 36810857 PMCID: PMC9944283 DOI: 10.1038/s41467-023-36696-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 02/08/2023] [Indexed: 02/23/2023] Open
Abstract
The explorations to extend present chemical synthetic methods are of great importance to simplify synthetic routes of chemical species. Additionally, understanding the chemical reaction mechanisms is critical to achieve controllable synthesis for applications. Here, we report the on-surface visualization and identification of a phenyl group migration reaction of 1,4-dimethyl-2,3,5,6-tetraphenyl benzene (DMTPB) precursor on Au(111), Cu(111) and Ag(110) substrates. With the combination of bond-resolved scanning tunneling microscopy (BR-STM), noncontact atomic force microscopy (nc-AFM) and density functional theory (DFT) calculations, the phenyl group migration reaction of DMTPB precursor is observed, forming various polycyclic aromatic hydrocarbons on the substrates. DFT calculations reveal that the multiple-step migrations are facilitated by the hydrogen radical attack, inducing cleavage of phenyl groups and subsequent rearomatization of the intermediates. This study provides insights into complex surface reaction mechanisms at the single molecule level, which may guide the design of chemical species.
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8
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On-surface synthesis of disilabenzene-bridged covalent organic frameworks. Nat Chem 2023; 15:136-142. [PMID: 36344816 PMCID: PMC9836936 DOI: 10.1038/s41557-022-01071-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Accepted: 09/21/2022] [Indexed: 11/09/2022]
Abstract
Substituting carbon with silicon in organic molecules and materials has long been an attractive way to modify their electronic structure and properties. Silicon-doped graphene-based materials are known to exhibit exotic properties, yet conjugated organic materials with atomically precise Si substitution have remained difficult to prepare. Here we present the on-surface synthesis of one- and two-dimensional covalent organic frameworks whose backbones contain 1,4-disilabenzene (C4Si2) linkers. Silicon atoms were first deposited on a Au(111) surface, forming a AuSix film on annealing. The subsequent deposition and annealing of a bromo-substituted polyaromatic hydrocarbon precursor (triphenylene or pyrene) on this surface led to the formation of the C4Si2-bridged networks, which were characterized by a combination of high-resolution scanning tunnelling microscopy and photoelectron spectroscopy supported by density functional theory calculations. Each Si in a hexagonal C4Si2 ring was found to be covalently linked to one terminal Br atom. For the linear structure obtained with the pyrene-based precursor, the C4Si2 rings were converted into C4Si pentagonal siloles by further annealing.
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9
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Wang T, Berdonces-Layunta A, Friedrich N, Vilas-Varela M, Calupitan JP, Pascual JI, Peña D, Casanova D, Corso M, de Oteyza DG. Aza-Triangulene: On-Surface Synthesis and Electronic and Magnetic Properties. J Am Chem Soc 2022; 144:4522-4529. [PMID: 35254059 PMCID: PMC8931755 DOI: 10.1021/jacs.1c12618] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
![]()
Nitrogen
heteroatom doping into a triangulene molecule allows tuning
its magnetic state. However, the synthesis of the nitrogen-doped triangulene
(aza-triangulene) has been challenging. Herein, we report the successful
synthesis of aza-triangulene on the Au(111) and Ag(111) surfaces,
along with their characterizations by scanning tunneling microscopy
and spectroscopy in combination with density functional theory (DFT)
calculations. Aza-triangulenes were obtained by reducing ketone-substituted
precursors. Exposure to atomic hydrogen followed by thermal annealing
and, when necessary, manipulations with the scanning probe afforded
the target product. We demonstrate that on Au(111), aza-triangulene
donates an electron to the substrate and exhibits an open-shell triplet
ground state. This is derived from the different Kondo resonances
of the final aza-triangulene product and a series of intermediates
on Au(111). Experimentally mapped molecular orbitals match with DFT-calculated
counterparts for a positively charged aza-triangulene. In contrast,
aza-triangulene on Ag(111) receives an extra electron from the substrate
and displays a closed-shell character. Our study reveals the electronic
properties of aza-triangulene on different metal surfaces and offers
an approach for the fabrication of new hydrocarbon structures, including
reactive open-shell molecules.
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Affiliation(s)
- Tao Wang
- Donostia International Physics Center, 20018 San Sebastián, Spain
- Centro de Fisica de Materiales CFM/MPC, CSIC-UPV/EHU, 20018 San Sebastián, Spain
| | - Alejandro Berdonces-Layunta
- Donostia International Physics Center, 20018 San Sebastián, Spain
- Centro de Fisica de Materiales CFM/MPC, CSIC-UPV/EHU, 20018 San Sebastián, Spain
| | | | - Manuel Vilas-Varela
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | | | - Jose Ignacio Pascual
- CIC NanoGUNE BRTA, 20018 San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain
| | - Diego Peña
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - David Casanova
- Donostia International Physics Center, 20018 San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain
| | - Martina Corso
- Donostia International Physics Center, 20018 San Sebastián, Spain
- Centro de Fisica de Materiales CFM/MPC, CSIC-UPV/EHU, 20018 San Sebastián, Spain
| | - Dimas G. de Oteyza
- Donostia International Physics Center, 20018 San Sebastián, Spain
- Centro de Fisica de Materiales CFM/MPC, CSIC-UPV/EHU, 20018 San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain
- Nanomaterials and Nanotechnology Research Center (CINN), CSIC-UNIOVI-PA; 33940 El Entrego, Spain
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10
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Kumar A, Banerjee K, Ervasti MM, Kezilebieke S, Dvorak M, Rinke P, Harju A, Liljeroth P. Electronic Characterization of a Charge-Transfer Complex Monolayer on Graphene. ACS NANO 2021; 15:9945-9954. [PMID: 34028269 PMCID: PMC8223480 DOI: 10.1021/acsnano.1c01430] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 05/19/2021] [Indexed: 06/12/2023]
Abstract
Organic charge-transfer complexes (CTCs) formed by strong electron acceptor and strong electron donor molecules are known to exhibit exotic effects such as superconductivity and charge density waves. We present a low-temperature scanning tunneling microscopy and spectroscopy (LT-STM/STS) study of a two-dimensional (2D) monolayer CTC of tetrathiafulvalene (TTF) and fluorinated tetracyanoquinodimethane (F4TCNQ), self-assembled on the surface of oxygen-intercalated epitaxial graphene on Ir(111) (G/O/Ir(111)). We confirm the formation of the charge-transfer complex by dI/dV spectroscopy and direct imaging of the singly occupied molecular orbitals. High-resolution spectroscopy reveals a gap at zero bias, suggesting the formation of a correlated ground state at low temperatures. These results point to the possibility to realize and study correlated ground states in charge-transfer complex monolayers on weakly interacting surfaces.
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Affiliation(s)
- Avijit Kumar
- School
of Basic Sciences, Indian Institute of Technology
Bhubaneswar, Jatni, 752050 Khurda, India
- Department
of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | - Kaustuv Banerjee
- Department
of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | - Mikko M. Ervasti
- Department
of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | | | - Marc Dvorak
- Department
of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | - Patrick Rinke
- Department
of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | - Ari Harju
- Department
of Applied Physics, Aalto University, FI-00076 Aalto, Finland
- Varian
Medical Systems Finland, FI-00270 Helsinki, Finland
| | - Peter Liljeroth
- Department
of Applied Physics, Aalto University, FI-00076 Aalto, Finland
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11
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Fan Q, Yan L, Tripp MW, Krejčí O, Dimosthenous S, Kachel SR, Chen M, Foster AS, Koert U, Liljeroth P, Gottfried JM. Biphenylene network: A nonbenzenoid carbon allotrope. Science 2021; 372:852-856. [DOI: 10.1126/science.abg4509] [Citation(s) in RCA: 140] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 04/14/2021] [Indexed: 01/06/2023]
Affiliation(s)
- Qitang Fan
- Department of Chemistry, Philipps-Universität Marburg, 35032 Marburg, Germany
| | - Linghao Yan
- Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | - Matthias W. Tripp
- Department of Chemistry, Philipps-Universität Marburg, 35032 Marburg, Germany
| | - Ondřej Krejčí
- Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | | | - Stefan R. Kachel
- Department of Chemistry, Philipps-Universität Marburg, 35032 Marburg, Germany
| | - Mengyi Chen
- Department of Chemistry, Philipps-Universität Marburg, 35032 Marburg, Germany
| | - Adam S. Foster
- Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, 920-1192 Kanazawa, Japan
| | - Ulrich Koert
- Department of Chemistry, Philipps-Universität Marburg, 35032 Marburg, Germany
| | - Peter Liljeroth
- Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland
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12
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Merino P, Rosławska A, Grewal A, Leon CC, Gonzalez C, Kuhnke K, Kern K. Gold Chain Formation via Local Lifting of Surface Reconstruction by Hot Electron Injection on H 2(D 2)/Au(111). ACS NANO 2020; 14:15241-15247. [PMID: 33119271 PMCID: PMC7610521 DOI: 10.1021/acsnano.0c05507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The hexagonal close packed surface of gold shows a 22 × 3 "herringbone" surface reconstruction which makes it unique among the (111) surfaces of all metals. This long-range energetically favored dislocation pattern appears in response to the strong tensile stress that would be present on the unreconstructed surface. Adsorption of molecular and atomic species can be used to tune this surface stress and lift the herringbone reconstruction. Here we show that herringbone reconstruction can be controllably lifted in ultrahigh vacuum at cryogenic temperatures by precise hot electron injection in the presence of hydrogen molecules. We use the sharp tip of a scanning tunneling microscope (STM) for charge carrier injection and characterization of the resulting chain nanostructures. By comparing STM images, rotational spectromicroscopy and ab initio calculations, we show that formation of gold atomic chains is associated with release of gold atoms from the surface, lifting of the reconstruction, dissociation of H2 molecules, and formation of surface hydrides. Gold hydrides grow in a zipper-like mechanism forming chains along the [11̅0] directions of the Au(111) surface and can be manipulated by further electron injection. Finally, we demonstrate that Au(111) terraces can be transformed with nearly perfect terrace selectivity over distances of hundreds of nanometers.
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Affiliation(s)
- P. Merino
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D70569, Stuttgart, Germany
- Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Inés de la Cruz 3, E28049, Madrid, Spain
- Instituto de Física Fundamental, CSIC, Serrano 121, E28006, Madrid, Spain
| | - A. Rosławska
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D70569, Stuttgart, Germany
| | - A. Grewal
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D70569, Stuttgart, Germany
| | - C. C. Leon
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D70569, Stuttgart, Germany
| | - C. Gonzalez
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Facultad de Ciencias, Universidad Autónoma de Madrid, E28049 Madrid, Spain
- Departamento de Física de Materiales, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Instituto de Magnetismo Aplicado UCM-ADIF, Vía de Servicio A-6, 900, E-28232 Las Rozas de Madrid, Spain
| | - K. Kuhnke
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D70569, Stuttgart, Germany
| | - K. Kern
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D70569, Stuttgart, Germany
- Institut de Physique, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
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13
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Sokolović I, Reticcioli M, Čalkovský M, Wagner M, Schmid M, Franchini C, Diebold U, Setvín M. Resolving the adsorption of molecular O 2 on the rutile TiO 2(110) surface by noncontact atomic force microscopy. Proc Natl Acad Sci U S A 2020; 117:14827-14837. [PMID: 32527857 PMCID: PMC7334520 DOI: 10.1073/pnas.1922452117] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Interaction of molecular oxygen with semiconducting oxide surfaces plays a key role in many technologies. The topic is difficult to approach both by experiment and in theory, mainly due to multiple stable charge states, adsorption configurations, and reaction channels of adsorbed oxygen species. Here we use a combination of noncontact atomic force microscopy (AFM) and density functional theory (DFT) to resolve [Formula: see text] adsorption on the rutile [Formula: see text](110) surface, which presents a longstanding challenge in the surface chemistry of metal oxides. We show that chemically inert AFM tips terminated by an oxygen adatom provide excellent resolution of both the adsorbed species and the oxygen sublattice of the substrate. Adsorbed [Formula: see text] molecules can accept either one or two electron polarons from the surface, forming superoxo or peroxo species. The peroxo state is energetically preferred under any conditions relevant for applications. The possibility of nonintrusive imaging allows us to explain behavior related to electron/hole injection from the tip, interaction with UV light, and the effect of thermal annealing.
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Affiliation(s)
- Igor Sokolović
- Institute of Applied Physics, Technische Universität Wien, 1040 Vienna, Austria
| | - Michele Reticcioli
- Institute of Applied Physics, Technische Universität Wien, 1040 Vienna, Austria
- Faculty of Physics, University of Vienna, 1090 Vienna, Austria
- Center for Computational Materials Science, University of Vienna, 1090 Vienna, Austria
| | - Martin Čalkovský
- Institute of Applied Physics, Technische Universität Wien, 1040 Vienna, Austria
- Institute of Physical Engineering, Brno University of Technology, 616 69 Brno, Czech Republic
| | - Margareta Wagner
- Institute of Applied Physics, Technische Universität Wien, 1040 Vienna, Austria
- Central European Institute of Technology, Brno University of Technology, 612 00 Brno, Czech Republic
| | - Michael Schmid
- Institute of Applied Physics, Technische Universität Wien, 1040 Vienna, Austria
| | - Cesare Franchini
- Faculty of Physics, University of Vienna, 1090 Vienna, Austria
- Center for Computational Materials Science, University of Vienna, 1090 Vienna, Austria
- Dipartimento di Fisica e Astronomia, Università di Bologna, 40127 Bologna, Italy
| | - Ulrike Diebold
- Institute of Applied Physics, Technische Universität Wien, 1040 Vienna, Austria
| | - Martin Setvín
- Institute of Applied Physics, Technische Universität Wien, 1040 Vienna, Austria;
- Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, 180 00 Prague 8, Czech Republic
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14
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Wang R, He Z, Sokolov AV, Kurouski D. Gap-Mode Tip-Enhanced Raman Scattering on Au Nanoplates of Varied Thickness. J Phys Chem Lett 2020; 11:3815-3820. [PMID: 32340446 DOI: 10.1021/acs.jpclett.0c01021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Gold nanoplates (AuNPLs) enable the gap-mode configuration of tip-enhanced Raman spectroscopy (TERS). This allows for low-concentration molecular sensing and high-resolution imaging. Compared with non-gap-mode TERS, the gap plasmon provides significantly higher enhancement factors. In addition, AuNPLs exhibit a lightning rod or edge effect, further enhancing the laser field and increasing the spectroscopic sensitivity. In this study, we investigate the relationship between the thickness of AuNPLs and the intensity of the spontaneous Raman signal produced by 4-nitrobenzenethiol, a reporter molecule used in TERS. Our experimental and theoretical results show that the intensity of TERS spectra increases with an increase in the thickness of the AuNPLs. This study of the thickness dependence of AuNPL allows us to find a configuration with maximal nanoplasmonic effects. Moreover, the electromagnetic interaction of the AuNPL with the tip, positioned near the AuNPL's edge, results in a plasmonic nanoantenna configuration for field enhancement, with important promise for future applications to nanobioimaging and biosensing.
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15
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Liu X, Wang L, Li S, Rahn MS, Yakobson BI, Hersam MC. Geometric imaging of borophene polymorphs with functionalized probes. Nat Commun 2019; 10:1642. [PMID: 30967559 PMCID: PMC6456592 DOI: 10.1038/s41467-019-09686-w] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 03/22/2019] [Indexed: 11/16/2022] Open
Abstract
A common characteristic of borophene polymorphs is the presence of hollow hexagons (HHs) in an otherwise triangular lattice. The vast number of possible HH arrangements underlies the polymorphic nature of borophene, and necessitates direct HH imaging to definitively identify its atomic structure. While borophene has been imaged with scanning tunneling microscopy using conventional metal probes, the convolution of topographic and electronic features hinders unambiguous identification of the atomic lattice. Here, we overcome these limitations by employing CO-functionalized atomic force microscopy to visualize structures corresponding to boron-boron covalent bonds. Additionally, we show that CO-functionalized scanning tunneling microscopy is an equivalent and more accessible technique for HH imaging, confirming the v1/5 and v1/6 borophene models as unifying structures for all observed phases. Using this methodology, a borophene phase diagram is assembled, including a transition from rotationally commensurate to incommensurate phases at high growth temperatures, thus corroborating the chemically discrete nature of borophene. Borophene, or 2D boron, is highly polymorphic with many predicted lattice arrangements, complicating the identification of its atomic structure. Here, the authors use functionalized-tip scanning probe microscopy to directly resolve the atomic lattice structures of several borophene polymorphs.
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Affiliation(s)
- Xiaolong Liu
- Applied Physics Graduate Program, Northwestern University, Evanston, IL, 60208, USA
| | - Luqing Wang
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX, 77005, USA
| | - Shaowei Li
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Matthew S Rahn
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Boris I Yakobson
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX, 77005, USA.,Department of Chemistry, Rice University, Houston, TX, 77005, USA
| | - Mark C Hersam
- Applied Physics Graduate Program, Northwestern University, Evanston, IL, 60208, USA. .,Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA. .,Department of Chemistry, Northwestern University, Evanston, IL, 60208, USA. .,Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, IL, 60208, USA.
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16
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Centi G, Čejka J. Needs and Gaps for Catalysis in Addressing Transitions in Chemistry and Energy from a Sustainability Perspective. CHEMSUSCHEM 2019; 12:621-632. [PMID: 30648784 DOI: 10.1002/cssc.201802637] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 12/13/2018] [Indexed: 06/09/2023]
Abstract
Catalysis is undergoing a major transition resulting from significant changes in chemical and energy production. To honor the 50th anniversary of establishing the Jerzy Haber Institute of Catalysis and Surface Chemistry, this Essay discusses, from a forward-looking, personal and somewhat provocative perspective, the needs and gaps of catalysis to address the ongoing transition in chemistry and energy from a sustainability perspective. The focus is on a few selected aspects identified as crucial: i) The precise synthesis of catalytic materials, particularly focusing on mesoporous molecular sieves, metal-organic frameworks, and zeolites (particularly two-dimensional type); ii) advanced catalyst characterization methods; iii) new concepts and approaches needed in catalysis to meet the demands of a field of energy and chemistry in transition.
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Affiliation(s)
- Gabriele Centi
- University of Messina, ERIC aisbl and CASPE/INSTM, Dept.s MIFT-Industrial Chemistry, V.le F. Stagno D'Alcontres 31, 98166, Messina, Italy
| | - Jiří Čejka
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Science, Dolejškova 3, 182 23, Prague 8, Czech Republic
- Current address: Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, 128 43, Prague 2, Czech Republic
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17
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Chutora T, de la Torre B, Mutombo P, Hellerstedt J, Kopeček J, Jelínek P, Švec M. Nitrous oxide as an effective AFM tip functionalization: a comparative study. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2019; 10:315-321. [PMID: 30800570 PMCID: PMC6369984 DOI: 10.3762/bjnano.10.30] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 01/07/2019] [Indexed: 05/14/2023]
Abstract
We investigate the possibility of functionalizing Au tips by N2O molecules deposited on a Au(111) surface and their further use for imaging with submolecular resolution. First, we characterize the adsorption of the N2O species on Au(111) by means of atomic force microscopy with CO-functionalized tips and density functional theory (DFT) simulations. Subsequently we devise a method of attaching a single N2O to a metal tip apex and benchmark its high-resolution imaging and spectroscopic capabilities using FePc molecules. Our results demonstrate the feasibility of high-resolution imaging. However, we find an inherent asymmetry of the N2O probe-particle adsorption on the tip apex, in contrast to a CO tip reference. These findings are consistent with DFT calculations of the N2O- and CO tip apexes.
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Affiliation(s)
- Taras Chutora
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic
| | - Bruno de la Torre
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00 Prague, Czech Republic
| | - Pingo Mutombo
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00 Prague, Czech Republic
| | - Jack Hellerstedt
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00 Prague, Czech Republic
| | - Jaromír Kopeček
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00 Prague, Czech Republic
| | - Pavel Jelínek
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00 Prague, Czech Republic
| | - Martin Švec
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00 Prague, Czech Republic
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18
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Giessibl FJ. The qPlus sensor, a powerful core for the atomic force microscope. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:011101. [PMID: 30709191 DOI: 10.1063/1.5052264] [Citation(s) in RCA: 135] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 12/25/2018] [Indexed: 05/27/2023]
Abstract
Atomic force microscopy (AFM) was introduced in 1986 and has since made its way into surface science, nanoscience, chemistry, biology, and material science as an imaging and manipulating tool with a rising number of applications. AFM can be employed in ambient and liquid environments as well as in vacuum and at low and ultralow temperatures. The technique is an offspring of scanning tunneling microscopy (STM), where the tunneling tip of the STM is replaced by using a force sensor with an attached tip. Measuring the tiny chemical forces that act between the tip and the sample is more difficult than measuring the tunneling current in STM. Therefore, even 30 years after the introduction of AFM, progress in instrumentation is substantial. Here, we focus on the core of the AFM, the force sensor with its tip and detection mechanism. Initially, force sensors were mainly micro-machined silicon cantilevers, mainly using optical methods to detect their deflection. The qPlus sensor, originally based on a quartz tuning fork and now custom built from quartz, is self-sensing by utilizing the piezoelectricity of quartz. The qPlus sensor allows us to perform STM and AFM in parallel, and the spatial resolution of its AFM channel has reached the subatomic level, exceeding the resolution of STM. Frequency modulation AFM (FM-AFM), where the frequency of an oscillating cantilever is altered by the gradient of the force that acts between the tip and the sample, has emerged over the years as the method that provides atomic and subatomic spatial resolution as well as force spectroscopy with sub-piconewton sensitivity. FM-AFM is precise; because of all physical observables, time and frequency can be measured by far with the greatest accuracy. By design, FM-AFM clearly separates conservative and dissipative interactions where conservative forces induce a frequency shift and dissipative interactions alter the power needed to maintain a constant oscillation amplitude of the cantilever. As it operates in a noncontact mode, it enables simultaneous AFM and STM measurements. The frequency stability of quartz and the small oscillation amplitudes that are possible with stiff quartz sensors optimize the signal to noise ratio. Here, we discuss the operating principles, the assembly of qPlus sensors, amplifiers, limiting factors, and applications. Applications encompass unprecedented subatomic spatial resolution, the measurement of forces that act in atomic manipulation, imaging and spectroscopy of spin-dependent forces, and atomic resolution of organic molecules, graphite, graphene, and oxides.
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Affiliation(s)
- Franz J Giessibl
- Institute of Experimental and Applied Physics, University of Regensburg, Universitätsstrasse 31, D-93040 Regensburg, Germany
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19
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Colazzo L, Mohammed MSG, Dorel R, Nita P, García Fernández C, Abufager P, Lorente N, Echavarren AM, de Oteyza DG. On-surface synthesis of heptacene on Ag(001) from brominated and non-brominated tetrahydroheptacene precursors. Chem Commun (Camb) 2018; 54:10260-10263. [PMID: 30152499 PMCID: PMC6136266 DOI: 10.1039/c8cc04402c] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Achieving the Ag(001)-supported synthesis of heptacene from two related reactants reveals the effect of the presence of Br atoms on the reaction process.
Achieving the Ag(001)-supported synthesis of heptacene from two related reactants reveals the effect of the presence of Br atoms on the reaction process. The properties of reactants, intermediates and end-products are further characterized by scanning tunneling microscopy and spectroscopy.
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Affiliation(s)
- Luciano Colazzo
- Donostia International Physics Center (DIPC), 20018 San Sebastián, Spain.
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20
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Hellerstedt J, Cahlík A, Švec M, de la Torre B, Moro-Lagares M, Chutora T, Papoušková B, Zoppellaro G, Mutombo P, Ruben M, Zbořil R, Jelinek P. On-surface structural and electronic properties of spontaneously formed Tb 2Pc 3 single molecule magnets. NANOSCALE 2018; 10:15553-15563. [PMID: 30087975 DOI: 10.1039/c8nr04215b] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The single molecule magnet (SMM) bis(phthalocyaninato)terbium(iii) (TbPc2) has received significant and increasing attention as an exemplar system for realizing molecule-based spin electronics. Attaining higher nuclearity via multi-decker TbPc systems has remained an outstanding challenge, as known examples of Tb2Pc3 systems are only those containing Pc rings with substituents (e.g. alkyl, alkoxyl). Here we report on the spontaneous formation of Tb2Pc3 species from TbPc2 precursors via sublimation in ultrahigh vacuum (UHV) onto an Ag(111) surface. The presence of Tb2Pc3 molecules on the surface are inspected using scanning probe microscopy with submolecular resolution supported by density functional theory (DFT) calculations and additional chemical analysis. We observe the selective presence of a Kondo resonance (30 K) in the Tb2Pc3 species, that we attribute to differences in the orientation of the internal molecular ligands. Formation of triple-decker complexes offers new possibilities to study and control magnetic interactions not accessible with standard TbPc2 molecules.
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Affiliation(s)
- Jack Hellerstedt
- Institute of Physics of the Czech Academy of Sciences, v.v.i., Cukrovarnická 10, 162 00 Praha 6, Czech Republic.
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21
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de la Torre B, Švec M, Hapala P, Redondo J, Krejčí O, Lo R, Manna D, Sarmah A, Nachtigallová D, Tuček J, Błoński P, Otyepka M, Zbořil R, Hobza P, Jelínek P. Non-covalent control of spin-state in metal-organic complex by positioning on N-doped graphene. Nat Commun 2018; 9:2831. [PMID: 30026582 PMCID: PMC6053383 DOI: 10.1038/s41467-018-05163-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 06/08/2018] [Indexed: 11/09/2022] Open
Abstract
Nitrogen doping of graphene significantly affects its chemical properties, which is particularly important in molecular sensing and electrocatalysis applications. However, detailed insight into interaction between N-dopant and molecules at the atomic scale is currently lacking. Here we demonstrate control over the spin state of a single iron(II) phthalocyanine molecule by its positioning on N-doped graphene. The spin transition was driven by weak intermixing between orbitals with z-component of N-dopant (pz of N-dopant) and molecule (dxz, dyz, dz2) with subsequent reordering of the Fe d-orbitals. The transition was accompanied by an electron density redistribution within the molecule, sensed by atomic force microscopy with CO-functionalized tip. This demonstrates the unique capability of the high-resolution imaging technique to discriminate between different spin states of single molecules. Moreover, we present a method for triggering spin state transitions and tuning the electronic properties of molecules through weak non-covalent interaction with suitably functionalized graphene.
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Affiliation(s)
- Bruno de la Torre
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 16200, Prague 6, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Martin Švec
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 16200, Prague 6, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Prokop Hapala
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 16200, Prague 6, Czech Republic
| | - Jesus Redondo
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 16200, Prague 6, Czech Republic
| | - Ondřej Krejčí
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 16200, Prague 6, Czech Republic
| | - Rabindranath Lo
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague 6, Czech Republic
| | - Debashree Manna
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague 6, Czech Republic
| | - Amrit Sarmah
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague 6, Czech Republic
| | - Dana Nachtigallová
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague 6, Czech Republic
| | - Jiří Tuček
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Piotr Błoński
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic
| | - Radek Zbořil
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic.
| | - Pavel Hobza
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic.
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague 6, Czech Republic.
| | - Pavel Jelínek
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 16200, Prague 6, Czech Republic.
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czech Republic.
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22
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Ebeling D, Šekutor M, Stiefermann M, Tschakert J, Dahl JEP, Carlson RMK, Schirmeisen A, Schreiner PR. Assigning the absolute configuration of single aliphatic molecules by visual inspection. Nat Commun 2018; 9:2420. [PMID: 29925833 PMCID: PMC6010418 DOI: 10.1038/s41467-018-04843-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 05/30/2018] [Indexed: 12/23/2022] Open
Abstract
Deciphering absolute configuration of a single molecule by direct visual inspection is the next step in compound identification, with far-reaching implications for medicinal chemistry, pharmacology, and natural product synthesis. We demonstrate the feasibility of this approach utilizing low temperature atomic force microscopy (AFM) with a CO-functionalized tip to determine the absolute configuration and orientation of a single, adsorbed [123]tetramantane molecule, the smallest chiral diamondoid. We differentiate between single enantiomers on Cu(111) by direct visual inspection, and furthermore identify molecular dimers and molecular clusters. The experimental results are confirmed by a computational study that allowed quantification of the corresponding intermolecular interactions. The unique toolset of absolute configuration determination combined with AFM tip manipulation opens a route for studying molecular nucleation, including chirality-driven assembly or reaction mechanisms.
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Affiliation(s)
- Daniel Ebeling
- Institute of Applied Physics, Justus-Liebig University, Heinrich-Buff-Ring 16, 35392, Giessen, Germany.
| | - Marina Šekutor
- Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 17, 35392, Giessen, Germany.
| | - Marvin Stiefermann
- Institute of Applied Physics, Justus-Liebig University, Heinrich-Buff-Ring 16, 35392, Giessen, Germany
| | - Jalmar Tschakert
- Institute of Applied Physics, Justus-Liebig University, Heinrich-Buff-Ring 16, 35392, Giessen, Germany
| | - Jeremy E P Dahl
- Stanford Institute for Materials and Energy Sciences, Stanford, CA, 94305, USA
| | - Robert M K Carlson
- Stanford Institute for Materials and Energy Sciences, Stanford, CA, 94305, USA
| | - André Schirmeisen
- Institute of Applied Physics, Justus-Liebig University, Heinrich-Buff-Ring 16, 35392, Giessen, Germany.
| | - Peter R Schreiner
- Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 17, 35392, Giessen, Germany.
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