0000000001040265

AUTHOR

L. Chang

showing 3 related works from this author

Ab initio calculations for the F-center transfer and R centers in SrF2

2013

We have simulated the F-center transfer and R center in SrF2 crystal by using density functional theory (DFT) with a hybrid B3PW description of exchange and correlation. Our calculations show that the F-center diffusion barrier is equal to 1.84 eV. During the F-center transfer, the trapped electron is more delocalized than that in the regular F-center case, and the gap between defect level and conduction bands (CB) in the a-spin state decreases. The formation energy calculations of R center show the trend of F centers to aggregate in SrF2. During the F-center aggregation, a considerable covalency forms between two neighboring fluorine vacancies with trapped electrons. Three incompletely pai…

Electron pairValence (chemistry)General Computer ScienceChemistryGeneral Physics and AstronomyGeneral ChemistryElectronic structureComputational MathematicsDelocalized electronMechanics of MaterialsAtomic electron transitionAb initio quantum chemistry methodsGeneral Materials ScienceDensity functional theoryAtomic physicsElectronic band structureComputational Materials Science
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Ab Initio Calculations of Hydroxyl Impurities in CaF2

2012

OH– in CaF2 crystal and the (111) surface have been studied by using density functional theory (DFT) with hybrid exchange potentials, namely, DFT-B3PW. Three bulk and 20 surface OH– configurations ...

Surface (mathematics)CrystalGeneral EnergyChemistryComputational chemistryImpurityAb initio quantum chemistry methodsPhysical chemistryDensity functional theoryPhysical and Theoretical ChemistrySurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsThe Journal of Physical Chemistry C
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Ab Initio Calculations of the Transfer and Aggregation of F Centers in CaF2

2012

The F center and R center in CaF2 crystals have been studied by using density functional theory (DFT) with a hybrid B3PW description of exchange and correlation. Our calculations show that the F-center diffusion barrier is equal to 1.67 eV. During the F-center transfer, the trapped electron is more delocalized than that in the regular F-center case, and the gap between defect level and CB in the α-spin state decreases. The surface F-center investigation shows the trend of F centers to locate near the surface. The association energy calculations of R centers indicate stable aggregations of isolated F centers. During the F-center aggregation, a considerable covalency forms between two neighbo…

Electron pairValence (chemistry)Diffusion barrierChemistrychemistry.chemical_elementElectronSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsDelocalized electronGeneral EnergyAb initio quantum chemistry methodsFluorineDensity functional theoryPhysical and Theoretical ChemistryAtomic physicsThe Journal of Physical Chemistry C
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