Search results for "MgAl2O4"

showing 4 items of 4 documents

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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Up-conversion and Photoluminescence in Er3+ Single Crystal MgAl-spinel

2015

Abstract Traditional and up-conversion luminescence of MgAl 2 O 4 single crystal doped with erbium ions obtained by the Verneuil method has been investigated. The time resolved spectral measurements of the green and red up-conversion luminescence bands show that a build-up part is present in the up-conversion luminescence kinetics. This means that energy transfer process is involved in the creation of the luminescence. Considering rather small concentration of Er 3+ in the material (0.12 mass %), the expected up-conversion mechanism should be excited state absorption since the average distance between erbium ions is high. The above-mentioned considerations suggest that clustering of the act…

energy transferMaterials sciencePhotoluminescenceDopingSpinelAnalytical chemistrychemistry.chemical_elementPhysics and Astronomy(all)engineering.materialIonerbiumErbiumMgAl2O4chemistryActivator (phosphor)engineeringup-conversion luminescenceLuminescenceSingle crystalPhysics Procedia
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Low-temperature studies of Cr 3+ ions in natural and neutron-irradiated g-Al spinel

2020

This study was supported by a grant from Latvian Council of Science (agreement No. LZP-2018/1-0214).

Materials sciencePhotoluminescencePhysics and Astronomy (miscellaneous)Analytical chemistryGeneral Physics and Astronomychemistry.chemical_elementengineering.material01 natural sciencesIonlaw.inventionlaw0103 physical sciences:NATURAL SCIENCES:Physics [Research Subject Categories]Neutronfast neutronsIrradiation010306 general physicsElectron paramagnetic resonance010302 applied physicsMagnesiumSpinelNeutron temperaturechemistryMgAl2O4photoluminescence spectraengineeringLow Temperature Physics
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Hybrid density functional calculations of hyperfine coupling tensor for hole-type defects in MgAl2O4

2020

This work has been performed within the framework of the EUROfusion Enabling Research project: ENR-MFE19.ISSP-UL-02 “Advanced experimental and theoretical analysis of defect evolution and structural disordering in optical and dielectric materials for fusion application”. The views and opinions expressed herein do not necessarily reflect those of the European Commission.

Nuclear and High Energy PhysicsMaterials scienceMgAl2O4 (spinel)02 engineering and technologyType (model theory)engineering.material010402 general chemistry01 natural sciencesMolecular physicsResonance (particle physics)Spectral linelaw.inventionParamagnetismlaw:NATURAL SCIENCES:Physics [Research Subject Categories]TensorElectron paramagnetic resonanceInstrumentationHole-type defects (V-centres)Relaxation (NMR)Spinel021001 nanoscience & nanotechnology3. Good health0104 chemical sciencesHybrid DFT calculations (B3LYP)engineering0210 nano-technologyNuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
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