Article
Chemistry, Multidisciplinary
Ryuto Yasui, Daiki Shimizu, Kenji Matsuda
Summary: The single-molecular conductance between two pi-conjugated wires with and without a radical substituent has been compared. The study found that the radical-substituted wire has significantly higher conductance than the methyl-substituted reference, despite the fact that only a small portion of the radical is distributed on the wire. This study demonstrates the potential of radical substituents in achieving high conductivity in molecular wires.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Editorial Material
Chemistry, Multidisciplinary
Ryuto Yasui, Daiki Shimizu, Kenji Matsuda
Summary: This study compares the single-molecular conductance between pi-conjugated wires with and without a radical substituent. The results show that the radical-substituted wire has 3.2 times higher conductance than the methyl-substituted reference. This study demonstrates the potential of radical substituents to achieve high conductivity in molecular wires.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Nanoscience & Nanotechnology
Si-Yuan Guan, Zhuan-Yun Cai, Zi-Wei Ma, De-Yin Wu, Zhong-Qun Tian
Summary: This study investigates the Au-n-octanedithiol-Au molecular junction (Au-SC8S-Au) using density functional theory combined with the nonequilibrium Green's function approach. The relationship between the binding structures at the interface and the single-molecule quantum conductance of n-octanedithiol (SC8S) in a gold nanogap is established through theoretical calculations. Different models of Au-SC8S-Au nanogaps are designed to understand the electron transport mechanism in single molecular nanojunctions. The calculated results show variations in conductance and bond fractures depending on the specific model and bond strength.
Article
Nanoscience & Nanotechnology
Quyen Van Nguyen, Nhat Pham Van, Huong Le Thi, Giang Le Truong
Summary: We report a quantitative analysis of conductance in tunneling junctions based on r-conjugated oligophenyleneimine (OPI) wires incorporated with thieno[2,3-b]thiophene (TT23) or thieno[3,2-b]thiophene (TT32) units. The results show that the conductance in linear r-conjugated TT32-OPI-n junctions is much greater than in nonlinear r-conjugated TT23-OPI-n junctions, primarily due to an increase in electronic coupling Gamma.
ACS APPLIED NANO MATERIALS
(2022)
Article
Biology
Nisha Arora, Jagadish Prasad Hazra, Sabyasachi Rakshit
Summary: Proteins, including individual ones and complexes, play important roles as force-sensors in responding to mechanical cues. Research suggests that protein complexes exhibit distinct mechanical responses to force compared to individual force-sensors.
COMMUNICATIONS BIOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Jin-Cheng Shu, Mao-Sheng Cao, Yan-Lan Zhang, Yu-Ze Wang, Quan-Liang Zhao, Xiao-Yong Fang, Shu-Hui Yang, Yong Qin, Jie Yuan
Summary: Atomic-molecular engineering is an effective method for precisely manipulating the microstructures and components of materials at the micro-nano scale, allowing for flexible control of their electromagnetic response. In this study, graphene microlaminates with a multi-layer structure were fabricated using atomic cluster engineering and oxidative molecular layer deposition. By adjusting the cycles of poly(3,4-ethylenedioxythiophene), the microlaminates exhibited tunable electromagnetic loss, with an attenuation constant of 160. Based on this, multifunctional antennas were developed, which achieved frequency-selective response and efficient energy harvesting from the signal source, as well as the recycling of waste heat and mechanical energy. This study opens up new possibilities for information transmission and artificial intelligence in the future.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Alberto Hijano, Stefan Ilic, F. Sebastian Bergeret
Summary: Josephson junctions exhibit a phase shift in their current-phase relation, leading to anomalous supercurrent flow. The Andreev interferometers, consisting of a mesoscopic conductor coupled to the junction, also show a finite phase shift effect. By considering different realizations of the junction, such as structures with spin-orbit coupling or spin-split superconductors, the quasiparticle current in the interferometer can be calculated to observe the anomalous component at finite phase shift.
Article
Materials Science, Multidisciplinary
C. K. Chan, S. D. Yeh, C. C. Chang, C. Y. Tu, I. C. Yang, K. L. Chang, C. W. Luo, C. S. Hwang
Summary: The study introduces a new type of leak element manufactured using femtosecond laser micromachining technology, which can solve the problems of serious outgassing at the sealing interface and low baking temperature. This device, which is reusable and performs as effectively as gasket-type leak elements, can be widely applied to various vacuum technologies and applications.
Article
Chemistry, Inorganic & Nuclear
Yuya Tanaka, Aki Okamoto, Shintaro Fujii, Tomoaki Nishino, Munetaka Akita
Summary: In this study, a new organometallic molecular wire was designed and its electrochemical properties and single-molecule conductance were investigated experimentally and computationally. The results show that the molecular wire exhibits excellent conductivity and can be connected to gold electrodes through C-H activation and formation of Au-C bonds.
INORGANICA CHIMICA ACTA
(2023)
Article
Biochemistry & Molecular Biology
Manuela Lanzafame, Giulia Branca, Claudia Landi, Mingyue Qiang, Bruno Vaz, Tiziana Nardo, Debora Ferri, Manuela Mura, Sebastian Iben, Miria Stefanini, Fiorenzo A. Peverali, Luca Bini, Donata Orioli
Summary: CSA and CSB proteins play key roles in the TC-NER pathway, removing UV-induced DNA lesions, and are also involved in other cellular pathways that may explain neurodegeneration and aging features in CS. This study identified a chromatin-associated protein complex containing CS that regulates rRNA transcription, shedding light on how CSA modulates rRNA transcription. Furthermore, impairment of FECH functionality leads to reduced RNAP1 occupancy on rDNA promoter and abnormal accumulation of 18S rRNA, contributing to the understanding of CS and EPP pathologies.
NUCLEIC ACIDS RESEARCH
(2021)
Article
Chemistry, Physical
Abhay Ram Balakrishnan, R. Shankar, S. Vijayakumar
Summary: Metal complexes of the form C5H5N -[C---N]-X-[C---C]n- C5H5N, where X = Ag, Au, Co, Cu and n = 1,2,3, were studied using Density Functional Theory methods to analyze their structural and conducting properties. The study found that pyridine terminated metal complexes showed significantly increased HOMO energies leading to lower transport barriers, as well as notably reduced HOMO-LUMO energy gaps compared to previous reports of polyyne chains. Additionally, positively charged polyyne-metal complexes exhibited a larger reduction in BLA.
COMPUTATIONAL AND THEORETICAL CHEMISTRY
(2021)
Article
Materials Science, Multidisciplinary
Caichao Wang, Yan Zhu, Kang Xu, Shuhong Sun, Mingrong Dong, Jinkun Liu, Yongmao Hu
Summary: Semiconductors Ag8SnS6 (ATS) nanoparticles were synthesized using a simple one-pot method, and semiconductors Ag8SnS6-xSex (ATSSe) (x = 0.0, 0.2, 0.4, 0.6, 0.8) nanoparticles were formed by adding Se during the ATS process. The ATS nanoparticles were mainly triangle in shape with grain sizes ranging from 15 - 60 nm, and the addition of Se resulted in the formation of ATSSe nanoparticles. Phase transformation from rhombohedral crystalline ATS to cubic ATSe was observed for Se substitution ratios x in the range of 0.2 - 0.8. The band gap of ATSSe nanoparticles ranged from 1.16 - 0.85 eV. This finding suggests that Se substitution is an effective method to regulate the band gap and structure of ATS.
Review
Chemistry, Multidisciplinary
Alessandra Serva, Nicolas Dubouis, Alexis Grimaud, Mathieu Salanne
Summary: The recent discovery of water-in-salt electrolytes has led to a resurgence in research on aqueous batteries, with a focus on expanding the electrochemical window. The speciation of water in these electrolytes differs from that in conventional aqueous solutions, leading to altered interfacial properties. By using a small amount of water in nonaqueous electrolytes, researchers have been able to control interface properties and expand the electrochemical window of aqueous electrolytes.
ACCOUNTS OF CHEMICAL RESEARCH
(2021)
Article
Physics, Multidisciplinary
Bruno Focassio, Tanna E. R. Fiuza, Jefferson Bettini, Gabriel R. Schleder, Murillo H. M. Rodrigues, Joao B. Souza Junior, Edson R. Leite, Adalberto Fazzio, Rodrigo B. Capaz
Summary: Using in situ high-resolution transmission electron microscopy and density functional theory, this study reports the formation and rupture of ZrO2 atomic ionic wires. It is found that under tensile stress, the system favors the spontaneous formation of oxygen vacancies, which is a critical step in the formation of monatomic bridges. The vacancies exhibit ductilelike behavior at this length scale, which is unexpected for ionic systems.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Physical
Jacques Kumutima, Xin-Qiu Yao, Donald Hamelberg
Summary: This study investigates the catalytic mechanism of unmodified and modified CypD using molecular dynamics simulations and analyzes the conformational dynamics. The results show that both unmodified and modified CypD lower the isomerization free energy barrier, supporting their catalytic activity. The phosphorylation and acetylation modifications have different effects on CypD's catalytic activity, which is due to significant conformational changes in different functional states.
JOURNAL OF PHYSICAL CHEMISTRY B
(2022)
Article
Nanoscience & Nanotechnology
Khalid Quertite, Hanna Enriquez, Nicolas Trcera, Azzedine Bendounan, Andrew J. Mayne, Gerald Dujardin, Abdallah El Kenz, Abdelilah Benyoussef, Yannick J. Dappe, Abdelkader Kara, Hamid Oughaddou
Summary: This work investigates the electron-induced modification of NaCl thin film on Ag(110) surface. Electron beam bombardment causes desorption and formation of Cl vacancy defects on NaCl surface, which are observed using low energy electron diffraction and scanning tunneling microscopy. Auger electron spectroscopy confirms the effect of electron exposure on NaCl thin films, while density functional theory and STM simulation provide further confirmation. The presence of Cl vacancy leads to an increase in adhesion energy and charge transfer between NaCl film and Ag substrate.
Article
Multidisciplinary Sciences
Kirill Vasilev, Benjamin Doppagne, Tomas Neuman, Anna Roslawska, Herve Bulou, Alex Boeglin, Fabrice Scheurer, Guillaume Schull
Summary: The authors demonstrate the internal Stark effect by observing spectral shifts in the fluorescence spectrum of a phthalocyanine molecule caused by electrostatic fields generated within the molecule itself. This phenomenon of tuning chromophores' optical properties using electrostatic fields is known as the internal Stark effect (ISE) and plays a crucial role in optimizing complex functions in living organisms. By sequentially removing central protons from a free-base phthalocyanine chromophore with a scanning tunneling microscope, the authors were able to measure the Stark shift in the emission energy caused by the charges confined within the chromophore.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Pablo Diaz-Rodriguez, Miguel Panizo-Laiz, Cesar Gonzalez, Roberto Iglesias, Ignacio Martin-Bragado, Raquel Gonzalez-Arrabal, Jose Manuel Perlado, Ovidio Pena-Rodriguez, Antonio Rivera
Summary: In this paper, an enhanced hydrogen permeation effect along grain boundaries in tungsten is reported. Experimental measurements and simulations support the observation that grain boundaries act as preferential migration pathways for hydrogen atoms, which has significant implications in reducing hydrogen retention in various applications.
EMERGENT MATERIALS
(2022)
Article
Chemistry, Physical
Alberto Castellano-Soria, Jesus Lopez-Sanchez, Cecilia Granados-Miralles, Maria Varela, Elena Navarro, Cesar Gonalez, Pilar Marin
Summary: Fe3C/few-layered graphene core/shell nanoparticles embedded in a carbon matrix are synthesized using a novel surfactant sol-gel strategy. The resulting product shows high magnetic response and chemical stability.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
D. Fernandez-Pello, M. A. Cerdeira, J. Suarez-Recio, R. Gonzalez-Arrabal, R. Iglesias, C. Gonzalez
Summary: In this paper, ab initio simulations were conducted to analyze the synergistic behavior of diverse defects in W, including self-interstitial atoms (SIA) and light impurity atoms (LIA) such as He and H. The influence of a W(110)/W(112) grain boundary (GB) on the coexisting defects was studied and compared with bulk results. The results showed that GBs act as trapping sites for SIAs and LIAs, and the interaction between He and H is weak. The behavior of defects in GBs differs from that in the bulk, and the presence of LIAs strongly affects the preferred orientation of SIA dumbbells. Additionally, the mobility of defects along the GB was assessed, and it was found that SIAs tend to move along the interfacial grooves to recombine with vacancies.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Chemistry, Physical
Andrea Gerbi, Renato Buzio, Cesar Gonzalez, Fernando Flores, Pedro L. de Andres
Summary: We propose a phase-space ab-initio formalism to calculate the current-voltage relationship of Ballistic Electron Emission Spectroscopy in a metal-semiconductor interface. The injection of electrons or holes under direct or reverse bias is studied. This research is important for determining the key technological characteristic of metal-semiconductor rectifying interfaces - the Schottky barrier.
APPLIED SURFACE SCIENCE
(2023)
Article
Physics, Multidisciplinary
F. Ming, X. Wu, C. Chen, K. D. Wang, P. Mai, T. A. Maier, J. Strockoz, J. W. F. Venderbos, C. Gonzalez, J. Ortega, S. Johnston, H. H. Weitering
Summary: Adatoms on a Si(111) substrate form a triangular lattice with unpaired electrons. Doping the Sn layer results in a superconducting state, which may exhibit chiral d-wave symmetry. Experiments confirm a doping-dependent critical temperature, fully gapped order parameter, time-reversal symmetry breaking, and enhanced zero-bias conductance near superconducting domain edges.
Article
Chemistry, Physical
Yann Girard, Sarah Benbouabdellah, Outhmane Chahib, Cyril Chacon, Amandine Bellec, Vincent Repain, Jerome Lagoute, Yannick J. Dappe, Cesar Gonzalez, Wei-Bin Su
Summary: The coupling of graphene with cobalt allows for technological advances in spintronics. The study focuses on cobalt intercalation between graphene and a buffer layer, which results in cobalt islands covered by graphene. These islands exhibit distinct shapes and properties, including small atomic islands and flat cobalt nanodots encapsulated by graphene.
Article
Chemistry, Multidisciplinary
Julien Lavie, Van Binh Vu, Daniel Medina-Lopez, Yannick Dappe, Thomas Liu, Loic Rondin, Jean-Sebastien Lauret, Sylvain Latil, Stephane Campidelli
Summary: Carbon nanomaterials, such as fullerene, nanotubes, graphene, and graphene quantum dots (GQDs), have been extensively studied by the scientific community for over 30 years. The synthesis of GQDs can be achieved through top-down and bottom-up approaches, with the latter allowing better control over size and shape. In this study, rectangular-shaped GQDs containing up to 162 sp(2) carbon atoms were successfully synthesized without functionalization. The dispersion and optical properties of the GQDs were investigated using sodium deoxycholate surfactant in water. The larger GQDs showed better dispersibility, possibly due to the increased number of surfactant molecules on their surfaces.
HELVETICA CHIMICA ACTA
(2023)
Article
Nanoscience & Nanotechnology
Egzona Neziri, Wei Zhang, Alexander Smogunov, Andrew J. Mayne, Abdelkader Kara, Yannick J. Dappe, Hamid Oughaddou
Summary: We report on the structural properties of Bi on Au(110) using LEED, STM, and DFT calculations. Various reconstructions are observed at a Bi coverage lower than 1 ML, and we focus on the Bi/Au(110)-c(2 x 2) reconstruction (at 0.5 ML) and Bi/Au(110)-(3 x 3) structure (at 0.66 ML). We propose models for both structures based on STM measurements and confirm them further using DFT calculations.
Article
Physics, Multidisciplinary
Song Jiang, Tomas Neuman, Remi Bretel, Alex Boeglin, Fabrice Scheurer, Eric Le Moal, Guillaume Schull
Summary: A scanning tunneling microscope was used to investigate the fluorescence of a charged molecule (quinacridone) adsorbed on a metallic sample covered with sodium chloride. The fluorescence from both neutral and positively charged species was observed and analyzed using hyperresolved fluorescence microscopy. A many-body model was developed based on the analysis of voltage, current, and spatial dependences of fluorescence and electron transport features. This model reveals that the charge states of quinacridone can vary transiently or permanently depending on the voltage and substrate properties.
PHYSICAL REVIEW LETTERS
(2023)
Article
Multidisciplinary Sciences
Song Jiang, Tomas Neuman, Alex Boeglin, Fabrice Scheurer, Guillaume Schull
Summary: In this study, the intrinsic optoelectronic properties of graphene nanoribbons (GNRs) were explored using a scanning tunneling microscope-based method. By transferring the GNRs onto a partially insulating surface, luminescence quenching effects were prevented and localized dark excitons associated with the topological end states of the GNRs were observed.
Article
Chemistry, Multidisciplinary
Sergii Snegir, Yannick J. Dappe, Dmytro Sysoiev, Thomas Huhn, Elke Scheer
Summary: This study investigates the structure and properties of a self-assembled monolayer on highly oriented pyrolytic graphite using scanning tunneling microscopy. The results show that the triazatriangulenium cations form hexagonally packed structures driven by the interaction with the graphite lattice. The monolayer consists of TATA(+) with and without BF4- counterions. The cationic TATA(+) exhibits a higher appearance compared to the neutral TATA-BF4.
Article
Physics, Multidisciplinary
Meryem Bouaziz, Aymen Mahmoudi, Geoffroy Kremer, Julien Chaste, Cesar Gonzalez, Yannick J. Dappe, Francois Bertran, Patrick Le Fevre, Marco Pala, Fabrice Oehler, Jean-Christophe Girard, Abdelkarim Ouerghi
Summary: Recently, intriguing physical properties have been discovered in anisotropic semiconductors, where the non-uniformity of the in-plane electronic band structure often stems from low crystal symmetry. Atomic chains, which represent the ultimate downsizing limit for electronic materials, have emerged as a frontier in the field of one-dimensional quantum materials. Investigating the electronic and structural properties of chain-like InTe is crucial for understanding its applications in devices such as thermoelectrics. In this study, we employed scanning tunneling microscopy/scanning tunneling spectroscopy (STS) and density functional theory (DFT) calculations to directly observe the in-plane structural anisotropy in tetragonal InTe. Our results demonstrate the presence of one-dimensional In1+ chains in InTe and reveal a bandgap of approximately 0.40 +/- 0.02 eV located at the M point of the Brillouin zone. Additionally, we observed line defects in our sample, which were attributed to vacancies in the In1+ chains along the c-axis, a common feature in other TlSe-like compounds. Our STS and DFT findings confirm that the presence of In1+ induces a localized gap state near the valence band maximum, explaining the high intrinsic p-type doping of InTe that we also confirmed using angle-resolved photoemission spectroscopy.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
M. N. Nair, I. Palacio, A. Mascaraque, E. G. Michel, A. Taleb-Ibrahimi, A. Tejeda, C. Gonzalez, A. Martin-Rodero, J. Ortega, F. Flores
Summary: This study reports an experimental and theoretical investigation of the electron-phonon coupling in α-Sn/Ge(111). The results show the presence of a significant electron-phonon interaction in a specific phase of α-Sn/Ge(111), which may play a role in the formation of different phases at low temperatures.
