Article
Chemistry, Physical
Juan J. J. Aucar, Alejandro F. F. Maldonado, Juan I. I. Melo
Summary: In this work, relativistic corrections to the electric field gradient (EFG) are presented, including spin-dependent corrections for the first time. The results show that these new corrections significantly improve the performance of the existing method and are in close agreement with calculations at the four-component Dirac-Hartree-Fock (4c-DHF) level. The accuracy of the EFG values obtained with this new method allows for the analysis of the electronic origin of relativistic effects using well-known nonrelativistic operators.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Jing Shang, Congxin Xia, Chun Tang, Chun Li, Yandong Ma, Yuantong Gu, Liangzhi Kou
Summary: The bending deformation of AgBiP2Se6 monolayers can manipulate the polarization direction and domain size, significantly improving the ferroelectric stability. This mechano-ferroelectric coupling represents a new mechanism for stabilization and polarization flip in 2D ferroelectrics, with potential applications in next-generation non-volatile storage devices.
NANOSCALE HORIZONS
(2021)
Article
Materials Science, Multidisciplinary
Zhigang Wu, John W. Lawson, Othmane Benafan
Summary: Nitinol (NiTi) is a commonly used shape memory alloy. A small change in the concentration of nickel and titanium has a dramatic effect on the martensitic transition temperature (MTT), leading to complications in manufacturing and applications of NiTi-based SMAs.
Article
Chemistry, Applied
Thibault Pariat, Pauline M. Verite, Denis Jacquemin, Julien Massue, Gilles Ulrich
Summary: A dual-emissive fluorophore, HBBODipic, with an Excited-State Intramolecular Proton Transfer (ESIPT) process has been described. It has been used for generating panchromatic white-emission and ratiometric detection of substrates.
Article
Physics, Applied
Shukai Yao, Babak Anasori, Alejandro Strachan
Summary: 2D rare-earth metal carbides (MXenes) with novel electronic and magnetic properties and potential as scalable 2D magnets were investigated. The effect of the U parameter on the stability and magnetism of different termination sites was studied. It was found that Mo2NdC2O2 and Mo2NdC2(OH)(2) exhibited magnetic properties regardless of termination and Hubbard U value.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Xue Dong, Yu-qian Liu, Xin-bo Liu, Sudip Pan, Zhong-hua Cui, Gabriel Merino
Summary: A new class of beryllium-boron clusters called beryllo-borospherenes are theoretically described in this paper. The addition of beryllium to the B-12 motif leads to significant structural modifications. Beryllium atoms form strong bonds with boron clusters through strong electrostatic and covalent interactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Physics, Fluids & Plasmas
Fengping Luo, Jia Huang, Qingyuan Liu, Zhiying Gao, Wei Ge, Fei Gao, Yugang Wang, Chenxu Wang
Summary: The coexistence of hydrogen and helium under vacancy supersaturation in the fusion environment affects the dynamic evolution of cavities and the swelling of structural materials. The stronger interaction between helium and vacancies is demonstrated compared to the interaction between hydrogen and vacancies. The repulsive interaction between hydrogen and helium around vacancies is confirmed. The presence of prior helium weakly influences the trapping of hydrogen but enhances its de-trapping, while the trapping of helium by vacancies is weakly influenced even in the presence of prior hydrogen. There is a critical density of prior hydrogen in vacancies, above which the de-trapping of helium is inhibited. This study provides important insights into cavity nucleation and hydrogen isotopes/helium retention in structural materials in the fusion environment.
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
Menglei Li, Shaobo Cheng, Wenbin Wang, Xing Li, Na Wang, Yimei Zhu
Summary: The study investigates oxide superlattices composed of hexagonal LuFeO3 (h-LuFeO3) and LuFe2O4 using density functional theory calculations. The coexistence of CO-induced polarizations and geometric polarizations in different periodicities of superlattices is observed, with LuFe2O4 favoring ferroelectric states over antiferroelectric states. Out-of-plane polarizations tend to align in parallel between h-LuFeO3 and LuFe2O4 layers, and the overall polarization increases with the ratio of h-LuFeO3. The influence of layered polarizations on the local electrostatic potential is minimal, except for small trends caused by CO-induced polarizations within FeO bilayers.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Chemistry, Physical
Stefan Juetten, Thomas Bredow
Summary: The transformation of Ti3O5 from the metastable lambda-phase to the stable beta-phase can be induced by external pressure, irradiation, or electric current. A recent study has revealed a selection rule for the photoinduced phase transition, showing that the transition only occurs when the pump pulse is applied to the ab plane. In this theoretical study, the possible reasons for this phenomenon are investigated, and the relative free energy of different phases under external pressure is calculated using density functional theory (DFT). The phase transition process is further examined by considering the formation and propagation of a beta-phase front in lambda-Ti3O5. The results confirm that phase transitions involving the ab interface are energetically favored, providing a rationalization for the experimental findings. The effect of pressure on the phase transition is attributed to the softening of specific phonon modes.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Computer Science, Interdisciplinary Applications
Nariman Abu el Kher, Israa Zeid, Nayla El-Kork, Mahmoud Korek
Summary: The electronic structure of alkaline-earth metal hydride cations SrH+ and BaH+ have been studied, with various spectroscopic parameters and rovibrational constants determined.
These substances play a crucial role in the absorption spectrum of the sun, making theoretical studies on them essential.
JOURNAL OF COMPUTATIONAL SCIENCE
(2021)
Article
Chemistry, Physical
Xiangyan Luo, Yixin Wang, Zean Tian, Jiajun Ma, Hong Yu, Quan Xie
Summary: This paper explores the stability and physical properties of double-walled carbon nanotubes and the bilayer graphene obtained from their unfolding. It examines the influence of tube diameter and chiral index on the stability and metallization trend of carbon nanotubes.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Materials Science, Multidisciplinary
Luke J. Wirth, Christopher Woodward, Amir A. Farajian
Summary: Advances in first principles methods are used to study the atom-vacancy exchanges near a screw dislocation in fcc Ni, revealing direction-dependent free energy profiles and temperature-dependent correlation effects. The dynamic approach shows intra-cell energy profile asymmetry related to dynamic geometry rearrangements. Despite absolute values of rate constants being similar, the HTST method generally underestimates rates by a factor of 2-5, partially explaining discrepancies between theoretical works and experiments in pipe diffusion diffusivities.
Article
Chemistry, Physical
Zhaolu Zhang, Guangyu He
Summary: In this study, experiments combined with density functional theory (DFT) were conducted to investigate the toughness enhancement mechanism of Ni-doped Cr2N coatings. The results showed that the Ni-doped Cr2N coating exhibited a single trigonal structure identified as a Cr2N-Ni solid solution. The hardness of the coating increased with Ni doping due to the increase in residual compressive stress and dislocation density. Interestingly, the elastic modulus decreased linearly with the increase in Ni doping, indicating improved ductility of the coating.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Multidisciplinary
Anthony C. Legon
Summary: The study investigates the radial potential energy of five axially symmetric halogen-bonded complexes at different intermolecular distances, calculating related spectroscopic constants and stretching modes. Different isomers and structural differences among the complexes are discussed using polynomial fitting and H-H function.