Search results for "First principle"

showing 3 items of 13 documents

2p x-ray absorption spectroscopy of 3d transition metal systems

2021

Abstract This review provides an overview of the different methods and computer codes that are used to interpret 2p x-ray absorption spectra of 3d transition metal ions. We first introduce the basic parameters and give an overview of the methods used. We start with the semi-empirical multiplet codes and compare the different codes that are available. A special chapter is devoted to the user friendly interfaces that have been written on the basis of these codes. Next we discuss the first principle codes based on band structure, including a chapter on Density Functional theory based approaches. We also give an overview of the first-principle multiplet codes that start from a cluster calculati…

Quantum chemistry calculationsComputer science02 engineering and technology01 natural sciencesTheoretical physicsAtomic and Molecular Physics0103 physical sciencesTaverneElectronicCluster (physics)Optical and Magnetic MaterialsPhysical and Theoretical ChemistryWave functionElectronic band structureMultipletComputingMilieux_MISCELLANEOUSDensity Functional TheorySpectroscopyX-ray absorption spectroscopy; Density Functional Theory; Quantum chemistry calculationsX-ray absorption spectroscopyRadiation010304 chemical physicsBasis (linear algebra)X-ray absorption spectroscopy021001 nanoscience & nanotechnologyCondensed Matter PhysicsAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic Materials[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]First principleDensity functional theoryand Optics0210 nano-technologyDen kondenserade materiens fysik
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Site symmetry approach applied to the supercell model of MgAl2O4 spinel with oxygen interstitials: Ab initio calculations

2018

This study has been carried out within the framework of the EUROfusion Consortium and has been provided funding from the Euratom research and training programme 2014-2018 under grant agreement No 633053. The authors are indebted to E.A. Kotomin, A.I. Popov and R. Vila for stimulating discussions. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Calculations have been performed using both the Marconi supercomputer system at the Computational Simulation Centre (Italy) and the Computer Center of St. Petersburg State University.

Single neutral oxygen interstitialMaterials scienceGeneral Computer ScienceBand gapSite symmetryGeneral Physics and Astronomy02 engineering and technologyengineering.material010402 general chemistry01 natural sciencesMolecular physicsPhysics::GeophysicsCrystalCondensed Matter::Materials ScienceLattice constantPerfect crystalAb initio quantum chemistry methods:NATURAL SCIENCES:Physics [Research Subject Categories]General Materials ScienceBulk modulusSpinelMgAl2O4 spinelGeneral Chemistry021001 nanoscience & nanotechnology0104 chemical sciencesComputational MathematicsMechanics of MaterialsengineeringWyckoff positions0210 nano-technologyFirst principles calculations
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Vacancy Defects in Ga2O3: First-Principles Calculations of Electronic Structure

2021

This research was funded by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (Grant No. AP08856540) as well as by the Latvian research council via the Latvian National Research Program under the topic ?High-Energy Physics and Accelerator Technologies?, Agreement No: VPP-IZM-CERN-2020/1-0002 for A.I. Popov. In addition, J. Purans is grateful to the ERAF project 1.1.1.1/20/A/057 while A. Platonenko was supported by Latvian Research Council No. LZP-2018/1-0214. The authors thank A. Lushchik and M. Lushchik for many useful discussions. The research was (partly) performed in the Institute of Solid State Physics, University of Latvia ISSP UL. ISSP UL as…

TechnologyDEEP DONOR02 engineering and technologyConductivityDFT01 natural sciencesOXYGENCrystalpoint defectsGeneral Materials ScienceDENSITY FUNCTIONAL THEORYGalliump-type conductivityMicroscopyQC120-168.85Condensed matter physicsMONOCLINICSTP TYPE CONDUCTIVITYELECTRONIC.STRUCTUREEngineering (General). Civil engineering (General)021001 nanoscience & nanotechnology3. Good healthCALCULATIONSβ-Ga<sub>2</sub>O<sub>3</sub>OXYGEN VACANCIES:NATURAL SCIENCES [Research Subject Categories]Density functional theoryElectrical engineering. Electronics. Nuclear engineeringTA1-20400210 nano-technologyPOINT DEFECTSFIRST PRINCIPLE CALCULATIONSβ-Ga2O3Materials scienceP-TYPE CONDUCTIVITYELECTRONIC STRUCTUREVACANCY DEFECTSchemistry.chemical_elementElectronic structureFIRST-PRINCIPLE DENSITY-FUNCTIONAL THEORIESGALLIUM COMPOUNDSArticleDENSITY-FUNCTIONAL-THEORYVacancy defect0103 physical sciences010306 general physicsΒ-GA2 O3QH201-278.5HYBRID EXCHANGEoxygen vacancyCrystallographic defectTK1-9971Descriptive and experimental mechanicschemistryGALLIUMdeep donorSupercell (crystal)DFT; β-Ga<sub>2</sub>O<sub>3</sub>; oxygen vacancy; deep donor; p-type conductivity; point defectsOXYGEN VACANCYMaterials
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