Article
Chemistry, Multidisciplinary
Tong Wu, Mingzi Sun, Bolong Huang
Summary: Current characterization techniques cannot unravel the detailed strain distributions on high-index facets, hindering the understanding of electroactivity origins. The lack of theoretical principles to quantify structural features on HIFs makes experimental efforts laborious, but exploring surface structural features and establishing a database of atomic strain distributions can promote efficient transition metal based electrocatalysts design and synthesis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Markus R. P. Pielmeier, Tom Nilges
Summary: Phosphorene and SnIP are two-dimensional and one-dimensional semiconductors formed from black phosphorus and SnI2, synthesized through mineralization and short way transport with similar yet different preparation methods. Investigating the formation mechanisms of these two compounds is of crucial importance for energy conversion, storage, and catalysis applications.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Enrique M. Arpa, Ines Corral
Summary: Unconjugated pterins are widely present and have various enzymatic functions, potentially participating in singlet oxygen, amino acid, and nucleotide photosensitization. Under UV-A light excitation, some of these pterins degrade, leading to hydrogen peroxide production. This process, occurring in vivo, contributes to oxidative stress and melanocyte destruction in vitiligo. Our study provides mechanistic insights into the formation of transient triplet species that trigger Type I and Type II photosensitizing processes and degradation. Through calculations, we demonstrate that 6-biopterin degradation in vitiligo patients' skin produces 6-formylpterin and subsequently 6-carboxypterin. The changes in photosensitizing potential with pH are attributed to modulation of excited-state redox potentials.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Materials Science, Multidisciplinary
Jianwei Xiao, Lingyu Zhu, Rui Wang, Chuang Deng, Zhaoxuan Wu, Yuntian Zhu
Summary: Twinning provides critical stress-relieving and flaw tolerance in body-centred cubic (BCC) transition metals (TMs) when dislocation plasticity is suppressed. Twin nucleation and growth mechanisms have been studied for over half a century without a consensus. Here, we use a reduced-constraint slip method to unveil the path to twin nucleation, growth and associated energy barriers in the entire BCC TM family.
Article
Materials Science, Multidisciplinary
Rakhima Balakhayeva, Abdirash Akilbekov, Zein Baimukhanov, Abay Usseinov, Sholpan Giniyatova, Maxim Zdorovets, Luydmila Vlasukova, A. I. Popov, Alma Dauletbekova
Summary: The synthesis of CdTe nanocrystals in a Wurtzite crystal phase was successfully achieved by electrochemical deposition into a prepared a-SiO2/Si-n template. The current-voltage characteristics measurement revealed n-type conductivity in the CdTe (WZ NC)/SiO2/Si system. Computer simulations using the CRYSTAL computer code showed good agreement between experimental and calculated lattice parameters, and also confirmed a direct bandgap at the Γ point of the Brillouin zone for the crystal.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Tony Stueker, Xiya Xia, Helmut Beckers, Sebastian Riedel
Summary: Pseudo-tetrahedral nitrido trifluorides equivalent to MF3 (M=Fe, Ru, Os) and square pyramidal nitrido tetrafluorides equivalent to MF4 (M=Ru, Os) were formed by reactions of free metal atoms with NF3 and isolated in solid neon at 5 K. Their IR spectra were analyzed with quantum-chemical calculations, revealing a high-spin (3)A(2) ground state for FeF3.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Shuqing Zhang, Sitong Huo, Xiaoyan Song, Xinping Zhang
Summary: Exfoliation of two-dimensional magnetic materials from non-vdW materials has become a topic of increased interest for the construction of 2D magnetic materials. Few-layer samples of non-vdW magnetic chromium tellurides, which possess high Curie temperatures, show promising applications in spintronics. The termination of the surface structures of few-layer chromium tellurides by either Cr or Te atoms remains under debate. Surface and exfoliation energy calculations reveal that the stability of the structures depends greatly on the chemical potential of Te atoms, and the few-layer sample with a Cr-terminated surface is easier to exfoliate than the one with both Te-terminated surfaces. Furthermore, the atomic number ratio of Cr to Te and the average magnetic moment of Cr atoms in few-layer samples can be used to identify different exfoliated structures.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Juan Tapia-P, Yipeng Cao, Jaime Gallego, Jorge M. Osorio-Guillen, Dane Morgan, Juan F. Espinal
Summary: The intrinsic defects of LaMnO3 and their effects on CO catalytic properties were studied. The most stable surface under reaction conditions was determined through calculations. The adsorption energies and the influence of intrinsic defects were also calculated, showing that O vacancies promote the interaction of CO on the surface while Mn vacancies favor the formation of carbonate species.
Article
Materials Science, Multidisciplinary
Luis E. Gonzalez, David J. Gonzalez
Summary: The static and dynamic properties of several bulk liquid 4d transition metals near their respective melting points have been evaluated using ab-initio molecular dynamics simulations. The results demonstrate the existence of ordered structures and special collective excitations, and further study several transport coefficients.
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Nilesh Vats, Devendra S. Negi, Deobrat Singh, Wilfried Sigle, Sabine Abb, Suman Sen, Sven Szilagyi, Hannah Ochner, Rajeev Ahuja, Klaus Kern, Stephan Rauschenbach, Peter A. van Aken
Summary: Studies have shown that specific species of atoms can catalyze atomic bond dissociation processes under electron beam, reducing the threshold energy for defect formation. This study finds that the presence of alkali and halide species together significantly enhances the etching activity of single-layer graphene under electron irradiation.
Article
Materials Science, Multidisciplinary
Alexander V. Bakulin, Lora S. Chumakova, Boris M. Elfimov, Svetlana E. Kulkova
Summary: The mechanisms of Ti and Si self-diffusion in Ti5Si3 compound were studied using the projector augmented-wave method within density functional theory. Migration and activation energies for Ti and Si atoms were calculated for vacancy and interstitial mechanisms. It was found that the smallest migration energy for Ti atom occurred in the interstitial mechanism, while for Si atom, it was 0.08 eV lower in the own-sublattice mechanism than in the interstitial one. The concentration of initial point defects and the preferred defects were determined. The temperature-dependent self-diffusion coefficients were calculated along two crystallographic directions, revealing that Ti atom diffuses faster than Si atom. The influence of metals of IVB-VIIB groups on Ti migration energy was also estimated, showing that most impurities increase migration energy and reduce Ti diffusivity in Ti5Si3.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Chemistry, Physical
Xavier Deraet, Jan Turek, Mercedes Alonso, Frederik Tielens, Bert M. M. Weckhuysen, Monica Calatayud, Frank De Proft
Summary: This paper investigates the adsorption behavior of single late transition metals on a defect-free anatase surface using periodic density functional theory calculations. The results reveal that the interaction strength between the transition metals and the support can be attributed to electron transfer, s-d orbital hybridization effects, or a synergistic effect between both factors. Palladium shows deviating adsorption behavior, which is likely associated with the lower dissociation enthalpy of the Pd-O bond. The reactivity of these systems is evaluated using the Fermi weighted density of states approach, and a model is proposed to predict the adsorption strength of CO on anatase-supported d-metal atoms.
Review
Spectroscopy
P. B. Armentrout
Summary: This review focuses on fragmentation studies of cationized amino acids and small peptides using guided ion beam tandem mass spectrometry (GIBMS). The results show that cationization generally leads to the dissociation of the intact biomolecule, with some exceptions. Proton cationization also leads to numerous dissociation channels. The importance of the deamidation of asparagine residues is explored through comparative studies of dipeptides. The thermochemistry of GIBMS is shown to correlate well with kinetic results from solution phase studies.
MASS SPECTROMETRY REVIEWS
(2023)
Review
Chemistry, Multidisciplinary
Hainan Sun, Xiaomin Xu, Yufei Song, Wei Zhou, Zongping Shao
Summary: This review focuses on the design strategies of heterogeneous electrocatalysts based on high-valence metal sites, emphasizing the importance of high-valence metal sites and structural modulation in water splitting. Advanced in situ and operando techniques are highlighted for tracking high-valence metal-based active sites, with proposed future research directions.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Organic
Xinhua Jia, Qiong Wang, Jianbiao Liu, Wenjuan Wang, Chuanzhi Sun, Fang Huang, Chong Yang, Dezhan Chen
Summary: The mechanism of N-heterocyclic carbene (NHC)-Cu-catalyzed selective allylation of N-benzylideneaniline with three allyl bromides was investigated using density functional theory (DFT) calculations. The results revealed a unique B(pin)-mediated Cu/B rearrangement mechanism, which is important for the rational design of reaction systems.
ORGANIC CHEMISTRY FRONTIERS
(2023)