Article
Materials Science, Multidisciplinary
B. G. Mendis, Q. M. Ramasse
Summary: The method proposed in the article effectively removes core hole distortion from electron energy loss spectra by calculating the electrodynamic work separating the incident electron from the core hole. The dynamic screening of the core hole is modeled using material dielectric properties and the resulting energy gain spectrum is deconvolved to obtain a fully screened spectrum. Although based on classical electrodynamics, the energy gain correction principle is consistent with quantum mechanics, but some assumptions made on the nature of the core hole are identified as flawed.
Article
Multidisciplinary Sciences
Giedrius Sasnauskas, Giedre Tamulaitiene, Gytis Druteika, Arturo Carabias, Arunas Silanskas, Darius Kazlauskas, Ceslovas Venclovas, Guillermo Montoya, Tautvydas Karvelis, Virginijus Siksnys
Summary: The TnpB proteins of the IS200/IS605 transposon family have been discovered as the smallest RNA-guided nucleases capable of targeted genome editing in eukaryotic cells. They are likely predecessors of Cas12 nucleases, which are widely used for targeted genome manipulation. This study presents the cryogenic-electron microscopy structures of the Deinococcus radiodurans TnpB-reRNA complex, revealing the basic architecture and molecular mechanism of TnpB nuclease for DNA target recognition and cleavage.
Article
Chemistry, Physical
Etienne Cuierrier, Pierre-Olivier Roy, Matthias Ernzerhof
Summary: Completely non-local approach, as one type of exchange-correlation energy approximation, has not been explored as much as other schemes. This approach uses electron density at every point to express the exchange-correlation energy, and constructs approximate exchange-correlation holes to handle the non-locality. However, the complex structure of the density makes it challenging to construct the corresponding function.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Peter Kovacs, Fabien Tran, Peter Blaha, Georg K. H. Madsen
Summary: This study systematically explores the space of generalized gradient approximation (GGA) and meta-GGA (mGGA) exchange approximations by training new functionals, aiming to improve accurate predictions of lattice parameter, cohesive energy, and bandgap. The trained functionals perform similarly to specialized functionals for bandgap predictions and outperform them for the other two properties.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Jared R. Williams, Nicolas Tancogne-Dejean, Carsten A. Ullrich
Summary: Time-dependent density-functional theory (TDDFT) is an efficient method for calculating optical spectra, providing insight into exciton dynamics by obtaining exciton wave functions and understanding the formation and dissociation of excitons in real time.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Chemistry, Physical
Reihan Nejatipour, Mehrdad Dadsetani
Summary: Using density functional theory and ELNES analysis, this study calculates and describes the sulfur K and L2,3 edge spectra of mercury-based defective chalcopyrites and its spinel structure, and compares with existing experimental spectra. Substituting gallium with aluminium alters the sulfur edge ELNES, reducing relative spectral intensities and shifting main peaks to higher energies. Covalency power and bond length contribute significantly to the dispersion of the edge spectra.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Yu Jin, Marco Govoni, Giulia Galli
Summary: This study presents a general framework to understand the optical cycle of spin defects in solids, with a focus on challenging singlet states. By predicting and interpreting experimental results, the study reveals the important role of specific phonons and non-adiabatic interactions in the absorption process.
NPJ COMPUTATIONAL MATERIALS
(2022)
Article
Optics
Ting Zhang, Neil Qiang Su
Summary: In this study, the hypercomplex Kohn-Sham (HCKS) formalism is explored and a new exact functional theory called 1-HCKS is developed as an alternative to traditional Kohn-Sham density functional theory (KS-DFT) and reduced density matrix functional theory (RDMFT) for dealing with strongly correlated systems. The unique feature of 1-HCKS is the introduction of hierarchical correlation orbitals that can capture strong correlation with fractional occupations, providing a balance between the rigidity of KS-DFT and flexibility of RDMFT. This approach eliminates the convergence and basis set dependence issues encountered in RDMFT.
Article
Materials Science, Multidisciplinary
J. C. Woicik, E. L. Shirley, C. Weiland, A. K. Rumaiz, C. A. Cardot, J. J. Kas, J. J. Rehr
Summary: The study reveals differences in crystal structure and photoelectron characteristics between gold and platinum, attributed to their differing atomic numbers.
Article
Energy & Fuels
Wenxu Shang, Wentao Yu, Xu Xiao, Yanyi Ma, Yi He, Peng Tan
Summary: In this work, a free-standing NiO@Co3S4 electrode with a core-shell structure is successfully fabricated and used in a hybrid Zn battery for the first time. This electrode exhibits improved performance in both pseudocapacitance and oxygen electrocatalysis compared to the pristine Co3S4 electrode. The hybrid Zn-Co/air battery with this electrode delivers high discharge and charge voltage plateaus, and has a long cycling life.
Article
Chemistry, Physical
Yiting Wang, Emil Proynov, Jing Kong
Summary: Exchange and correlation holes are fundamental quantum concepts for understanding electron interactions, with the exact exchange hole being of particular interest due to its rigorous derivation from first principles. This study develops an algorithm for computing the spherically averaged exact exchange hole and identifies the BR89 exchange hole as more suitable for isolated atoms. Further approximations for exchange holes are still in demand for various applications.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Abdul Rehman Akbar, Gangqiang Peng, Yongyi Li, Rashid Iqbal, Adil Saleem, Guohong Wang, Abdul Sammed Khan, Mumtaz Ali, Muhammad Tahir, Mohammed A. Assiri, Ghaffar Ali, Fude Liu
Summary: The fabrication of low-cost, effective, and highly integrated nanostructured materials for high-energy-density supercapacitors is highly desired. In this study, an activated carbon cloth (ACC) is designed as the functional scaffold for supercapacitors and modified with various nanomaterials. The resulting structured core-shell heterostructure ACC@NiCo@NiOOH@CoMoO4 electrode exhibits exceptional specific areal capacitance and cycling stability. Moreover, this electrode is developed into an asymmetric supercapacitor, demonstrating excellent areal capacitance, energy density, and power density with a high cycling life.
Article
Microscopy
Zahra Derikvandi, Mehrdad Dadsetani, Reihan Nejatipour
Summary: In this study, the effect of different termination groups on the energy loss near edge structure (ELNES) of carbon K edge in Mo2C MXene was investigated using first-principles calculations. The results showed that the spectral structures in Mo2CT2 were reproduced at higher energies compared to pristine Mo2C. The energy separation between the main peaks increased as the termination group changed from O to F and to OH, indicating a decrease in the Mo-C bond length. The comparison of ELNES spectra and the unoccupied densities of states (DOS) revealed the different origins of the structures at the carbon K edge.
Article
Chemistry, Physical
Etienne Cuierrier, Pierre-Olivier Roy, Rodrigo Wang, Matthias Ernzerhof
Summary: In this study, we consider the fourth-order term T-sigma of the spherically averaged exchange hole to approximate hybrid functionals and improve the calculation of exchange-correlation energy. By using machine learning and neural networks, a new functional is constructed based on the correlation between T-sigma and the nonlocality of the exchange hole, resulting in a significant improvement over previous methods.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Iulia Emilia Brumboiu, Thomas Fransson
Summary: The influence of core-hole delocalization on x-ray spectroscopy calculations is investigated using different methods. The study finds significant discrepancies between localized and delocalized core-holes, even with electron correlation effects considered.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
M. Dadsetani, B. Kianisadr, H. Nejatipour
JOURNAL OF ELECTRONIC MATERIALS
(2015)
Article
Chemistry, Multidisciplinary
Mehrdad Dadsetani, Hajar Nejatipour, Ali Ebrahimian
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2015)
Article
Engineering, Electrical & Electronic
Mehrdad Dadsetani, Ali Ebrahimian, Hajar Nejatipour
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2015)
Article
Nanoscience & Nanotechnology
Mehrdad Dadsetani, Hajar Nejatipour, Tahereh Nouri
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2015)
Article
Physics, Applied
Hajar Nejatipour, Mehrdad Dadsetani
INTERNATIONAL JOURNAL OF MODERN PHYSICS B
(2016)
Article
Optics
Hajar Nejatipour, Mehrdad Dadsetani
JOURNAL OF LUMINESCENCE
(2016)
Article
Engineering, Electrical & Electronic
Mehrdad Dadsetani, Reihan Nejatipour
JOURNAL OF ELECTRONIC MATERIALS
(2018)
Article
Microscopy
Mehrdad Dadsetani, Tahereh Nouri, Hajar Nejatipour
Article
Engineering, Electrical & Electronic
R. Momeni Feili, M. Dadsetani, R. Nejatipour, A. Ebrahimian
JOURNAL OF ELECTRONIC MATERIALS
(2020)
Article
Chemistry, Multidisciplinary
Samira Molaeipour, Mehrdad Dadsetani, Reihan Nejatipour
Summary: In this study, the electronic properties of titanium and zirconium MXene monolayers were investigated using the FP-LAPW and ELNES methods. The results show that the main spectral features occur at higher energies in the monolayers due to the shorter M-X bond lengths. The terminal groups affect the oscillator strengths and overall spectral shapes, as well as causing a red-shift in the main spectral features. The terminal substituents have a significant effect on the px + py states but do not affect the features caused by the pz character.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2022)
Article
Physics, Condensed Matter
Razieh Momeni Feili, Reihan Nejatipour, Mehrdad Dadsetani
Summary: The present study calculates and interprets the optical properties of Sc2CT2 and Hf2CO2 MXene semiconductors using a specific method and equation, revealing the presence of excitonic structures and spectral features in the energy loss function.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2023)
Article
Microscopy
Reihan Nejatipour, Mehrdad Dadsetani
Summary: This study examines the effect of local coordination and site symmetry on the electron energy structure of AgGaO2 polymorphs through ab initio calculations of the electron density of states and energy loss near edge structure (ELNES) analysis.
Article
Chemistry, Physical
Reihan Nejatipour, Mehrdad Dadsetani
Summary: Using density functional theory and ELNES analysis, this study calculates and describes the sulfur K and L2,3 edge spectra of mercury-based defective chalcopyrites and its spinel structure, and compares with existing experimental spectra. Substituting gallium with aluminium alters the sulfur edge ELNES, reducing relative spectral intensities and shifting main peaks to higher energies. Covalency power and bond length contribute significantly to the dispersion of the edge spectra.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Physics, Multidisciplinary
H. Nejatipour, M. Dadsetani
INDIAN JOURNAL OF PHYSICS
(2017)