The electronic and atomic properties of oxygen-vacancy dipoles and hydrogen
impurities were calculated. The band-gap of SrF2 for four different arrangements of
OV dipoles was found at 11.3eV when calculated using hybrid B3PW (Becke's
exchange functionals using Becke's 3-parameter method combined with the nonlocal
correlation functional of Perdew and Wang) and was essentially the same as
that for the perfect SrF2 crystal. On the basis of the calculated density of states, the
nature of the defect bands in the band structure can be well understood. Two kinds
of hydrogen impurity (HH
-, Hi
0) were also calculated using the B3PW method. The
corresponding electronic structure was presented and calculations were made of the
hyperfine constants at the Hi
0 impurity, which exhibited an unpaired electron, and
at its nearest-neighbour fluorine atoms. The results agreed well with experimental
data.
First-Principles Calculations of Oxygen-Vacancy Dipoles and Hydrogen
Impurities in SrF2. R.Jia, H.Shi, G.Borstel: Physical Review B, 2008, 78[22],
224101