New Center Formation in Silver Halide Crystals Doped with Sulphur
نویسندگان
چکیده
We employed the hybrid DFT-LCAO approach as implemented in the CRYSTAL code for 135 atom supercell calculations of O vacancies with trapped electrons (known as the F centers) in three cubic perovskite crystals: SrTiO3, PbTiO3 and PbZrO3. The local lattice relaxation, charge redistribution and defect energy levels in the optical gap are compared. We demonstrate how difference in a chemical composition of host materials leads to quite different defect properties.
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تاریخ انتشار 2008