Article
Chemistry, Multidisciplinary
Xinlei Yao, Maxime Vonesch, Maiwenn Combes, Jean Weiss, Xiaonan Sun, Jean-Christophe Lacroix
Summary: This study demonstrates the preparation of highly stable single-molecule junctions using diazonium grafting approach. The conductance of porphyrin oligomers is relatively efficient and influenced by the presence of cobalt center, showing a long stability around 10 seconds. Random telegraph signals easily record on/off states of SMJs, indicating the potential applications of this approach in constructing stable molecular junctions.
Article
Nanoscience & Nanotechnology
Xiao-Mei Li, Ya-Hao Wang, Jing-Wen Seng, Ju-Fang Zheng, Rui Cao, Yong Shao, Jing-Zhe Chen, Jian-Feng Li, Xiao-Shun Zhou, Bing-Wei Mao
Summary: Fabricating single-molecule diodes using asymmetric metal electrodes is a significant challenge, but the development of a z-piezo pulse-modulated STM-BJ technique in this study has enabled the construction of robust asymmetric junctions. The resulting asymmetric junctions exhibit rectifying behavior at the single-molecule level, with a decrease in single-molecule conductance when reversing bias voltage. This research provides a feasible approach for fabricating hybrid junctions based on asymmetric metal electrodes and investigating electron transport behavior.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Review
Nanoscience & Nanotechnology
S. Colonna, R. Flammini, F. Ronci
Summary: This paper reviews the research activity of the author's group in the field of silicene synthesis and properties, focusing on the interaction between silicon deposition and silicon substrate, and discussing the debated formation of silicene from unsaturated silicon compounds.
Article
Chemistry, Multidisciplinary
Kwan Ho Au-Yeung, Suchetana Sarkar, Tim Kuhne, Oumaima Aiboudi, Dmitry A. Ryndyk, Roberto Robles, Nicolas Lorente, Franziska Lissel, Christian Joachim, Francesca Moresco
Summary: Depending on its adsorption conformation, a zwitterionic single-molecule machine can act as a unidirectional rotor or a fast-drivable molecule vehicle (nanocar) on the Au(111) surface. The conformation can be selected by tuning the surface coverage. The inelastic tunneling excitation plays a role in both the rotation of the rotor and the movement of the nanocar under bias voltage pulses.
Article
Nanoscience & Nanotechnology
Shintaro Fujii, Enrique Montes, Haruna Cho, Yi Yue, Masaaki Koike, Tomoaki Nishino, Hector Vazquez, Manabu Kiguchi
Summary: In this paper, the tuning of the thermopower of single-molecule junctions of fullerene, 4,4'-bipyridine, and p-phenylenediamine using scanning tunneling microscopy-based break junction technique is demonstrated. The thermoelectric voltage of the junction is tuned by mechanically controlling the tip-electrode separation distance. The atomistic simulations illustrate the shifts in the conduction orbital energies induced by the mechanical compression of the junctions.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Junwoo Park, Mohamad S. Kodaimati, Lee Belding, Samuel E. Root, George C. Schatz, George M. Whitesides
Summary: This paper investigates the origin of hysteretic behavior in two-terminal molecular junctions made from an EGaIn electrode and self-assembled monolayers of alkanethiolates terminated in chelates (BIPY-MCl2). The study found that the hysteresis of conductance in these BIPY-MCl2 junctions only appears in an incoherent tunneling regime. The conductance characteristics of these junctions can be controlled by changing the applied voltage.
Article
Chemistry, Physical
Ruoning Li, Xue Zhang, Na Xue, Jie Li, Tianhao Wu, Zhen Xu, Yifan Wang, Na Li, Hao Tang, Shimin Hou, Yongfeng Wang
Summary: Metal-organic nanostructures on surfaces are structurally stable and have potential applications. Metal atoms can come from externally deposited metals or native surface atoms. Currently, these nanostructures mainly consist of Au or Cu, with fewer consisting of Ag. Further investigations are needed for accurate control of the desired nanostructures.
ACTA PHYSICO-CHIMICA SINICA
(2022)
Article
Chemistry, Multidisciplinary
Majed Alshammari, Alaa A. Al-Jobory, Turki Alotaibi, Colin J. Lambert, Ali Ismael
Summary: Through research, it has been discovered that single-molecule junctions formed from different materials can exhibit bi-thermal behavior, depending on the orientation of the molecule within the junction. This finding contributes to improving the efficiency of molecular-scale thermoelectric energy generators.
NANOSCALE ADVANCES
(2022)
Article
Materials Science, Multidisciplinary
Weixin Li, Jianmin Yan, Cong Wang, Ning Zhang, Tsz Hin Choy, Su Liu, Lei Zhao, Xiaoming Tao, Yang Chai
Summary: Printing is an additive manufacturing method that can reduce material costs and environmental contamination. We have developed a molecule-bridged graphene/silver composite for producing highly conductive and cost-effective paper-based electronics. This composite can replace part of the expensive silver, reduce costs, and maintain reasonable conductivity.
SCIENCE CHINA-MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Kai Zhang, Marie-Christine Hanf, Romain Bernard, Yves Borensztein, Hervei Cruguel, Andrea Resta, Yves Garreau, Alina Vlad, Alessandro Coati, Davide Sciacca, Bruno Grandidier, Mickael Derivaz, Carmelo Pirri, Philippe Sonnet, Reigis Stephan, Geoffroy Prevot
Summary: Through scanning tunneling microscopy (STM), surface X-ray diffraction (SXRD), and density functional theory, we have revealed a Ge-induced (root 109 x root 109)R +/- 24.5 degrees reconstruction on Ag(111). We have demonstrated the possibility of solving a giant surface reconstruction using SXRD and STM. The reconstructed structure consists of Ge pentagons, hexagons, and heptagons, with the inclusion of a few dispersed Ag atoms.
Article
Chemistry, Multidisciplinary
Andreas Jeindl, Jari Domke, Lukas Hoermann, Falko Sojka, Roman Forker, Torsten Fritz, Oliver T. Hofmann
Summary: The fabrication of nanomaterials involves self-organization processes of functional molecules on inorganic surfaces. By equipping molecules with functional groups, specific molecular arrangements can be obtained. However, the complexities of processes at interfaces can lead to unexpected structures, as shown in the example of a series of quinones on Ag(111). The study reveals a nonintuitive interplay of important interaction mechanisms, challenging the design of functional interfaces despite the ability to devise design principles for self-assembly of functionalized molecules.
Article
Chemistry, Multidisciplinary
Yujing Wei, Liang Li, Julia E. Greenwald, Latha Venkataraman
Summary: Understanding the relationship between molecular geometry and electronic properties of single-molecule junctions is challenging. In this study, we investigated this relationship by applying a sinusoidal modulation to the molecular junction electrode position. We found that junctions formed with molecules having different molecule-electrode interfaces exhibited statistically distinguishable Fourier-transformed conductances. Our findings suggest that voltage-modulated van der Waals interactions play a significant role in the conductance of single-molecule junctions.
Article
Biochemistry & Molecular Biology
Ziye Wu, Peng Cui, Mingsen Deng
Summary: This paper presents an effective strategy to enhance the multifunctionality and switching performance of diarylethene-based molecular devices. Through molecular engineering design and theoretical calculations, the transport behaviors of molecules with different substituents are investigated, and a rectification function that can be switched on/off through photoisomerization is proposed.
Article
Multidisciplinary Sciences
Zixiao Wang, Julio L. Palma, Hui Wang, Junzhi Liu, Gang Zhou, M. R. Ajayakumar, Xinliang Feng, Wei Wang, Jens Ulstrup, Alexei A. Kornyshev, Yueqi Li, Nongjian Tao
Summary: Single-molecule electrochemical science has made significant advancements in molecular electronics functions, particularly rectification. This article proposes an experimental and theoretical strategy for in situ rectification in symmetric molecular structures in an electrochemical environment. By independently controlling the electrochemical potential of the tip and substrate electrodes, single-molecule rectification is observed. The polarity and amplitude of the rectification can be tuned by varying the energy and electrolyte concentration. The study provides a promising approach for building controllable single-molecule rectifying devices without the need for asymmetric molecular structures.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Chemistry, Multidisciplinary
Junwoo Park, Lee Belding, Li Yuan, Maral P. S. Mousavi, Samuel E. Root, Hyo Jae Yoon, George M. Whitesides
Summary: This paper investigates the rectification mechanism in molecular tunneling junctions based on alkanethiolates terminated by a bipyridine group complexed with different metal ions. The study shows that the rectification behavior is determined by the accessibility of molecular orbitals at different bias voltages. The difference in tunneling mechanism at negative bias causes the variation in rectification ratio between the two types of junctions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Brent Lawson, Percy Zahl, Mark S. Hybertsen, Maria Kamenetska
Summary: Single-molecule circuits with group 8 metallocenes are formed without additional linker groups in scanning tunneling microscope-based break junction measurements. The nature of the gold-pi binding motif and its effect on molecular conductance and persistence characteristics during junction evolution are investigated. The interaction between the cyclopentadienyl rings of the metallocenes and the gold electrodes allows for extended conductance plateaus.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Materials Science, Multidisciplinary
Nongnuch Artrith, Jose Antonio Garrido Torres, Alexander Urban, Mark S. Hybertsen
Summary: This article presents a systematic method to determine parameters and optimize the errors of semilocal density-functional theory (DFT) methods for transition-metal oxides phase diagrams. By considering thermochemical data of a set of compounds and using leave-one-out cross validation, the proposed correction terms reduce the errors in the formation energies of binary and ternary oxides by up to 75% and achieve an error reduction of 30% using a simplified scheme.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Chemistry, Physical
Narendra P. Arasu, Hector Vazquez
Summary: Interfaces between metals and organic materials are crucial in molecular surface science, photovoltaics, or molecular electronics. This study presents a method for calculating interface parameters based on density functional theory calculations of small metal-molecule complexes. The generated parameter set is used in classical molecular dynamics simulations to gain insights into molecular degrees of freedom inaccessible through ab initio molecular dynamics simulations.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Chemistry, Physical
Hector Vazquez
Summary: A method is proposed to calculate the tunneling conductance of single molecule junctions using density functional theory. The method reduces computational cost significantly and allows for large-scale conductance calculations, providing a possibility to study the relationship between molecular structure and conductance.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Shintaro Fujii, Enrique Montes, Haruna Cho, Yi Yue, Masaaki Koike, Tomoaki Nishino, Hector Vazquez, Manabu Kiguchi
Summary: In this paper, the tuning of the thermopower of single-molecule junctions of fullerene, 4,4'-bipyridine, and p-phenylenediamine using scanning tunneling microscopy-based break junction technique is demonstrated. The thermoelectric voltage of the junction is tuned by mechanically controlling the tip-electrode separation distance. The atomistic simulations illustrate the shifts in the conduction orbital energies induced by the mechanical compression of the junctions.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Liang Li, Shayan Louie, Austin M. Evans, Elena Meirzadeh, Colin Nuckolls, Latha Venkataraman
Summary: Molecular one-dimensional topological insulators (1D TIs) that conduct through low-lying topological edge states have potential for nanoelectronic devices. To observe these effects at longer lengths, 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 increased electronic transmission. The longest oligo[7]emeraldine with doped topological states has over 106 enhancements in transmission compared to its pristine form.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Yujing Wei, Liang Li, Julia E. Greenwald, Latha Venkataraman
Summary: Understanding the relationship between molecular geometry and electronic properties of single-molecule junctions is challenging. In this study, we investigated this relationship by applying a sinusoidal modulation to the molecular junction electrode position. We found that junctions formed with molecules having different molecule-electrode interfaces exhibited statistically distinguishable Fourier-transformed conductances. Our findings suggest that voltage-modulated van der Waals interactions play a significant role in the conductance of single-molecule junctions.
Article
Materials Science, Multidisciplinary
Zhu Liang, Matthew R. Carbone, Wei Chen, Fanchen Meng, Eli Stavitski, Deyu Lu, Mark S. Hybertsen, Xiaohui Qu
Summary: A semisupervised machine learning method called RankAAE is developed and demonstrated for interpreting XANES spectra and discovering structure-spectrum relationships. The method constructs a one-to-one mapping between individual structure descriptors and spectral trends. It provides a robust and quantitative measure of the structure-spectrum relationship, decoupling intertwined spectral contributions from multiple structural characteristics.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Xiaoyun Pan, Enrique Montes, Wudmir Y. Rojas, Brent Lawson, Hector Vazquez, Maria Kamenetska
Summary: We demonstrate enhanced electronic transport through self-assembled dimer molecular junctions between gold electrodes. The per-molecule conductance of benzimidazole dimers is higher than that of monomers. Our calculations reveal that parallel stacking of two benzimidazoles is energetically favorable due to the large p system. We engineer imidazole derivatives with higher monomer conductance and promote cooperative assembly of more transparent dimer junctions, suggesting the potential of molecular devices based on self-assembled molecular layers.
Article
Physics, Multidisciplinary
Animesh Ghose, Mikhail Segal, Fanchen Meng, Zhu Liang, Mark S. Hybertsen, Xiaohui Qu, Eli Stavitski, Shinjae Yoo, Deyu Lu, Matthew R. Carbone
Summary: The importance of uncertainty quantification in machine learning methods applied to physical sciences has been highlighted. In this study, neural network ensembles are used to predict x-ray absorption spectra and their uncertainties for small molecules. The performance of the model demonstrates a quantitative correlation between errors and uncertainty estimates. This uncertainty-aware model has the capability to indicate out-of-sample predictions, allowing for integration with large-scale sampling and structure refinement techniques.
PHYSICAL REVIEW RESEARCH
(2023)
Correction
Chemistry, Multidisciplinary
Nicholas M. Orchanian, Sophia Guizzo, Michael L. Steigerwald, Colin Nuckolls, Latha Venkataraman
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Nicholas M. Orchanian, Sophia Guizzo, Michael L. Steigerwald, Colin Nuckolls, Latha Venkataraman
Summary: The study demonstrates that the reactivity of a kinetically inert transition metal complex can be altered by an external electric field for carbon-carbon coupling reactions. The findings highlight the significance of electric field effects in reaction chemistry and present a novel strategy for modulating organometallic reactivity.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Ilana B. Stone, Rachel L. Starr, Norah Hoffmann, Xiao Wang, Austin M. Evans, Colin Nuckolls, Tristan H. Lambert, Michael L. Steigerwald, Timothy C. Berkelbach, Xavier Roy, Latha Venkataraman
Summary: This study describes the Ullmann coupling of aryl iodides on rough gold surfaces, investigations of the reaction mechanism using experimental and theoretical methods reveal the influence of surface roughness and local electric fields on the reaction, providing important insights for understanding catalysis.
Article
Chemistry, Multidisciplinary
Zexin Jin, Qian Cheng, Austin M. Evans, Jesse Gray, Ruiwen Zhang, Si Tong Bao, Fengkai Wei, Latha Venkataraman, Yuan Yang, Colin Nuckolls
Summary: In this study, a modular approach was developed to construct pi-conjugated RA-2DPs with high electrical conductivity and high ion diffusion rates. These materials functioned as organic cathode materials with good rate performance and excellent cycling stability. Importantly, the improved design allowed for higher mass-loadings, enabling practical applications.
Article
Chemistry, Physical
Narendra P. Arasu, Hector Vazquez
Summary: This study describes a method for calculating interface parameters from small metal-molecule complexes based on reference density functional theory calculations, and applies it to develop a parameter set for metal-molecule-metal junctions. Nanosecond classical molecular dynamics simulations using the generated parameter set provide insights into molecular degrees of freedom.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)