Article
Chemistry, Multidisciplinary
Nicolas Neel, Joerg Kroeger
Summary: The study revealed that the formation of a chemical bond between a CO molecule and a Cu(111) surface is accompanied by bending of the molecular probe due to van der Waals attraction and Pauli repulsion, resulting in characteristic changes in the vertical force between CO and Cu(111) as a function of molecule-surface distance. Experimental data were successfully reproduced by model calculations, shedding new light on vertical-force extrema in scanning probe experiments.
Article
Chemistry, Multidisciplinary
Yuan Zhang, Daniel J. Trainer, Badri Narayanan, Yang Li, Anh T. Ngo, Sushila Khadka, Arnab Neogi, Brandon Fisher, Larry A. Curtiss, Subramanian K. R. S. Sankaranarayanan, Saw Wai Hla
Summary: By using a q+ atomic force microscopy at low temperature, researchers observed lateral force anisotropy of a sexiphenyl molecule moving on an atomically flat Ag(111) surface. The one-dimensional shape of the molecule was identified as the origin of this phenomenon, which was confirmed through molecular dynamics simulations. This finding may have significant implications for atomic scale frictional phenomena on materials surfaces.
Article
Chemistry, Multidisciplinary
Shantanu Mishra, Shadi Fatayer, Saleta Fernandez, Katharina Kaiser, Diego Pena, Leo Gross
Summary: We report the on-surface synthesis of a non-benzenoid triradical through dehydrogenation of truxene (C27H18) on coinage metal and insulator surfaces. The final product truxene-5,10,15-triyl (1) retains its open-shell quartet ground state on a two monolayer-thick NaCl layer on a Cu(111) surface, and its frontier orbital densities correspond to spin-split singly occupied molecular orbitals.
Article
Chemistry, Multidisciplinary
Qigang Zhong, Alexander Ihle, Sebastian Ahles, Hermann A. Wegner, Andre Schirmeisen, Daniel Ebeling
Summary: Constructing low-dimensional covalent assemblies with tailored size and connectivity is challenging but important in molecular electronics for tuning the properties of quantum materials. A versatile approach has been developed for building such structures block by block on a surface through highly selective tip-induced intermolecular reactions.
Article
Chemistry, Multidisciplinary
Katerina Vaxevani, Jingcheng Li, Stefano Trivini, Jon Ortuzar, Danilo Longo, Dongfei Wang, Jose Ignacio Pascual
Summary: The study shows that a proximity-induced superconducting gold film can sustain spin excitations of a FeTPP-Cl molecule for over 80 ns, which decreases with increasing film thickness. This suggests potential new routes for manipulating the spin lifetime of quantum spins on surfaces using proximitized gold electrodes.
Review
Physics, Multidisciplinary
Wenze Gao, Chi Zhang, Zheng Zhou, Wei Xu
Summary: This article summarizes recent progress in the synthesis of carbyne-like nanostructures with one-dimensional sp-carbon on surfaces, including polyynes, cumulenes, and organometallic polyynes. Scientific challenges and prospects are highlighted, encouraging scientists to explore the fabrication and characterization of single strands of carbyne in this young and promising research field.
Article
Chemistry, Multidisciplinary
Donglin Li, Luye Sun, Yuanqi Ding, Mengxi Liu, Lei Xie, Yinfu Liu, Lina Shang, Yangfan Wu, Hui-Jun Jiang, Lifeng Chi, Xiaohui Qiu, Wei Xu
Summary: This study focuses on the role of water molecules in driving chiral separation on the surface when RNA base uracil selfassembles into homochiral structures upon water exposure. The findings provide insights into the general role of water molecules in the origin of homochirality in living systems, with implications for other biologically relevant molecules such as amino acids and sugars.
Review
Chemistry, Physical
Chunlei Yang, Tianhui Su, Yanbo Hua, Liming Zhang
Summary: This review summarizes the latest results of electrochemical scanning probe microscopy techniques in studying the interfacial properties of electrocatalysts and photoelectrodes, and offers some perspectives on future research directions.
Article
Chemistry, Multidisciplinary
Leonard-Alexander Lieske, Mario Commodo, Jacob W. W. Martin, Katharina Kaiser, Vasiliki Benekou, Patrizia Minutolo, Andrea D'Anna, Leo Gross
Summary: This study used high-resolution atomic force microscopy and scanning tunneling microscopy to investigate the initial formation of soot in flames. The research revealed the atomic structure and orbital densities of single soot molecules, as well as the formation mechanisms of aromatic compounds through cross-linking and cyclodehydrogenation reactions. The findings also detected the presence of nonhexagonal rings in flame aromatics, indicating simultaneous growth through aromatic cross-linking/cyclodehydrogenation and hydrogen abstraction acetylene addition. Furthermore, the study identified three classes of open-shell π-radical species and their implications for soot formation and cleaner combustion.
Article
Chemistry, Multidisciplinary
Wenze Gao, Faming Kang, Xia Qiu, Zewei Yi, Lina Shang, Mengxi Liu, Xiaohui Qiu, Yi Luo, Wei Xu
Summary: The configuration of carbon allotropes in condensed phases, whether linear or cyclic, has long been a mystery. In this study, a molecule with a C-6 skeleton was designed to address this issue. The C-6 ring intermediate resulting from complete debromination was found to be energetically unstable at room temperature. It subsequently underwent a ring-opening process and polymerized into an organometallic polyyne.
Article
Chemistry, Multidisciplinary
Xunshan Liu, Adam Matej, Tim Kratky, Jesus Mendieta-Moreno, Sebastian Guenther, Pingo Mutombo, Silvio Decurtins, Ulrich Aschauer, Jascha Repp, Pavel Jelinek, Shi-Xia Liu, Laerte L. Patera
Summary: In this study, selective C-H activation of hexaazatriphenylene by Scholl reaction was reported for the first time, achieving dehydrogenative C-C couplings. The formation of one-dimensional polymers with a double-chain structure was revealed using low-temperature scanning tunneling microscopy and atomic force microscopy. Density functional theory calculations rationalized the growth process, highlighting the cooperative catalytic action of Na and Ag adatoms in steering the C-H selectivity for polymerization.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Benjamin Mallada, Qifan Chen, Taras Chutora, Ana Sanchez-Grande, Borja Cirera, Jose Santos, Nazario Martin, David Ecija, Pavel Jelinek, Bruno de la Torre
Summary: This study reveals that deliberately introducing atomic-scale defects into a specific anthracene-ethynylene pi-conjugated polymer can modify its inherent electronic and magnetic properties, affecting the material's performance. The results demonstrate a higher likelihood of forming low-dimensional defects at specific sites in polymers, offering new possibilities for engineering macroscopic defects in surface-synthesized conjugated polymers.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Materials Science, Multidisciplinary
Niko Oinonen, Lauri Kurki, Alexander Ilin, Adam S. Foster
Summary: This study proposes a machine learning model to address the challenge of interpreting atomic force microscope (AFM) image data. The model successfully extracts molecule graphs from simulated AFM images, but further work is needed to improve its robustness for real AFM images.
Review
Physics, Condensed Matter
Dong Han, Junfa Zhu
Summary: On-surface synthesis has emerged as an alternative to traditional in-solution synthesis, attracting extensive attention for its ability to fabricate nanoarchitectures with exotic properties. This method, conducted on atomically flat solid surfaces under ultrahigh vacuum, opens novel reaction pathways for chemical synthesis, leading to the fabrication of various low-dimensional nanostructures.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Chemistry, Multidisciplinary
Euihwan Do, Jae Whan Park, Oleksandr Stetsovych, Pavel Jelinek, Han Woong Yeom
Summary: In this study, the low-temperature structural distortion of a one-dimensional electronic system formed on Au-decorated vicinal silicon surfaces is unambiguously identified using high-resolution atomic force microscopy and scanning tunneling microscopy. The buckling of the step-edge Si chains, forming trimer unit cells, is found to be the most important structural element of this surface. This observation supports the recent model of rehybridized dangling bonds and contradicts the previously proposed antiferromagnetic spin ordering.
Article
Physics, Multidisciplinary
J. G. Vilhena, Remy Pawlak, Philipp D'Astolfo, Xunshan Liu, Enrico Gnecco, Marcin Kisiel, Thilo Glatzel, Ruben Perez, Robert Haener, Silvio Decurtins, Alexis Baratoff, Giacomo Prampolini, Shi-Xia Liu, Ernst Meyer
Summary: A combination of low temperature atomic force microscopy and molecular dynamics simulations showed that soft designer molecules exhibit a sidewinding motion on a gold surface. The flexibility of these molecules allows for a lowered diffusion energy barrier and results in ultralow friction.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Sebastian Scherb, Antoine Hinaut, Xuelin Yao, Alicia Goetz, Samir H. Al-Hilfi, Xiao-Ye Wang, Yunbin Hu, Zijie Qiu, Yiming Song, Klaus Muellen, Thilo Glatzel, Akimitsu Narita, Ernst Meyer
Summary: In this study, solution-synthesized graphene nanoribbons (GNRs) were successfully deposited on surfaces maintained in ultrahigh vacuum using high-vacuum electrospray deposition (HVESD) method. Submolecular imaging combined with Raman spectroscopy was used to characterize individual GNRs and confirm their chemical integrity. Furthermore, GNRs were deposited on nonmetallic HOPG and SiO2 surfaces, as well as on a KBr(001) surface, allowing the study of GNRs on substrates not accessible by on-surface synthesis.
Article
Chemistry, Multidisciplinary
Yujing Ma, Kazuma Sugawara, Yusuke Ishigaki, Kewei Sun, Takanori Suzuki, Shigeki Kawai
Summary: We successfully synthesized pyrrolopyrrole-bridged ladder oligomers from 11,11,12,12-tetrabromo-1,4,5,8-tetraaza-9,10-anthraquinodimethane molecules on Ag(111) using bond-resolved scanning tunneling microscopy. The non-dehydrogenative cyclization between pyrazine and ethynylene/cumulene groups has a low-activation barrier, forming dimeric oligomers containing dipyrazinopyrrolopyrrolopyrazine units and providing new insights into strain sensitivity in ladder-oligomer formation.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Remy Pawlak, Ernst Meyer, Khalid N. Anindya, Toshiki Shimizu, Jung-Ching Liu, Takumi Sakamaki, Rui Shang, Alain Rochefort, Eiichi Nakamura
Summary: The substitution of heteroatoms and non-benzenoid carbons in nanographene structure allows for atomic engineering of electronic properties. This study demonstrates the bottom-up synthesis of graphene nanoribbons with embedded BN-doped rubicene components using on-surface chemistry. The incorporation of BN heteroatoms results in an increased electronic band gap, providing opportunities for designing semiconducting graphene nanoribbons with optoelectronic properties.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Kewei Sun, Orlando J. Silveira, Yujing Ma, Yuri Hasegawa, Michio Matsumoto, Satoshi Kera, Ondrej Krejci, Adam S. Foster, Shigeki Kawai
Summary: Substituting carbon with silicon in organic molecules and materials is a challenging task, but in this study, the researchers successfully synthesized one- and two-dimensional covalent organic frameworks with atomically precise Si substitution. The structures were characterized using high-resolution scanning tunnelling microscopy and photoelectron spectroscopy, and it was found that each Si atom in a hexagonal C4Si2 ring was covalently linked to one terminal Br atom.
Article
Chemistry, Multidisciplinary
Xiushang Xu, Kewei Sun, Atsushi Ishikawa, Akimitsu Narita, Shigeki Kawai
Summary: Graphene nanoribbons and nanographenes synthesized on surfaces have great potential for studying magnetism in nano-spintronics. In this study, unprecedented 7-armchair GNRs with p-extended structures were synthesized and shown to exhibit Kondo resonances even on bare Au(111). The unique nonplanar termini formed by rearrangement reactions reduce the interaction with the Au(111) surface, allowing for spin localization and control of magnetism on metal substrates.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Zhao Liu, J. G. Vilhena, Ernst Meyer, Antoine Hinaut, Sebastian Scherb, Feng Luo, Junyan Zhang, Thilo Glatzel, Enrico Gnecco
Summary: Friction control and technological advancement are closely linked, and two-dimensional materials have unique characteristics for achieving quasi-frictionless contacts. Inspired by twistronics, we propose to use moire patterning to control superlubricity. Experimental and simulation results reveal a transition from superlubric to dissipative sliding regime in graphene moires on a Pt(111) surface at different twist angles, triggered by the normal force. This transition is caused by a novel mechanism at the superlattice level, where the moire tiles are manipulated in a highly dissipative shear process associated with the twist angle. The atomic-level details of this dissipation allow the bridging of different sliding regimes in a reversible manner, providing a subtle intrinsic control of superlubricity.
Article
Multidisciplinary Sciences
Krisztina Regos, Remy Pawlak, Xing Wang, Ernst Meyer, Silvio Decurtins, Gabor Domokos, Kostya S. Novoselov, Shi-Xia Liu, Ulrich Aschauer
Summary: Molecular self-assembly plays a crucial role in technology and biological systems. Predicting pattern formation in 2D molecular networks is challenging, but this study introduces a simplified hierarchical geometric model based on graph theory to predict extended network patterns. The model provides pattern classification and prediction within specific ranges, offering a different perspective on self-assembled molecular patterns and potential applications.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Multidisciplinary
Takahiro Kojima, Karan Patel, Shunpei Nobusue, Ahmed Mahmoud, Cong Xie, Takahiro Nakae, Shigeki Kawai, Kazuhiro Fukami, Hiroshi Sakaguchi
Summary: The introduction of functional groups into polymers in an asymmetric manner has great potential for creating novel electronic and magnetic properties. By utilizing low halogen-contaminated metal surfaces, a vectorial on-surface synthetic technique was developed, which allows isotactic polymerization of compass precursors without the need for chiral catalysts. The resulting isotactic polymers exhibit polar 2D crystalline structures and offer new insights into stereoregular control and crystal engineering.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
Jung-Ching Liu, Remy Pawlak, Xing Wang, Hongyan Chen, Philipp D'Astolfo, Carl Drechsel, Ping Zhou, Robert Haener, Silvio Decurtins, Ulrich Aschauer, Shi-Xia Liu, Wulf Wulfhekel, Ernst Meyer
Summary: Obtaining a robust superconducting state in atomically precise nanographene structures by proximity to a superconductor has been achieved on noble metals and metal oxides but not on superconductors. In this study, a synthetic method is presented to induce superconductivity of polymeric chains and nanographene adsorbed on a superconducting substrate covered by thin Ag films. The chemical structure of each subproduct formed on the superconducting Ag layer is characterized using atomic force microscopy, and the electronic properties of these nanostructures, consistently showing a superconducting gap, are elucidated by scanning tunneling spectroscopy.
ACS MATERIALS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Yiming Song, Ernst Meyer
Summary: In this Perspective, the recent advances in atomic friction of two-dimensional materials measured by friction force microscopy are presented. The main factors contributing to sliding friction between single asperity and a two-dimensional sheet are discussed, including material chemical identity, thickness, external load, sliding direction, velocity/temperature, and contact size. The latest progress of the more complex friction behavior of moire systems involving 2D layered materials is particularly focused on. The underlying mechanisms of these observed frictional characteristics during the sliding process are discussed through theoretical and computational studies, and a discussion and outlook on the perspective of this field are provided.
Article
Multidisciplinary Sciences
Chao Li, Christoph Kaspar, Ping Zhou, Jung-Ching Liu, Outhmane Chahib, Thilo Glatzel, Robert Haener, Ulrich Aschauer, Silvio Decurtins, Shi-Xia Liu, Michael Thoss, Ernst Meyer, Remy Pawlak
Summary: Electron-vibration coupling plays a critical role in the development of molecular electronics, spintronics, and quantum technologies. This study demonstrates the direct control of vibronic excitations in TBTAP molecules on the surface of Ag(111).
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Kewei Sun, Donglin Li, Takahito Kaihara, Satoshi Minakata, Youhei Takeda, Shigeki Kawai
Summary: In this study, nitrogen-doped nanographene and its dimer with an [18]annulene pore were synthesized through sequential reactions on the Ag(111) surface. The inner structure of the products was characterized using scanning tunneling microscopy, and the electronic states were investigated with scanning tunneling spectroscopy and theoretical calculations.
COMMUNICATIONS CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Kewei Sun, Kazuma Sugawara, Andrey Lyalin, Yusuke Ishigaki, Kohei Uosaki, Oscar Custance, Tetsuya Taketsugu, Takanori Suzuki, Shigeki Kawai
Summary: In this study, complex organometallic oligomers were systematically synthesized on Cu(111) through sequential ring opening and bonding of phenanthroline derivatives by multiple Cu atoms. Characterization using scanning tunneling microscopy and density functional theory calculations revealed the role of Cu adatoms in the chiral oligomers. Furthermore, the strength of the bonds against sliding friction was found to be sufficient.
