First-principles studies on electronic structures and absorption spectra of PbWO4 crystals with defect [V-Pb(2-)-V-O(2+)-V-Pb(2-)](2-)

摘要

Electronic structures and absorption spectra for perfect PbWO4 (PWO) crystal and the crystal containing aggregated defect [V-Pb(2-)-V-O(2+)-V-Pb(2-)](2-) have been calculated using density functional theory code CASTEP with the lattice structure optimized. The calculated absorption spectra of the PWO crystal containing the aggregated defect [VPb2--V-O(2+)-V-Pb(2-)](2-) exhibit two absorption bands peaking at 1.90eV (650nm) and 3.02eV (410nm). It is predicted that the 420 and 680nm absorption bands are related to the aggregated defect [V-Pb(2-)-V-O(2+)-V-Pb(2-)](2-) in the PWO crystal.