Bisbwo6: Properties Of A Mixed 5s/6s Lone-Pair-Electron System

We investigate the behavior of lone-pair electrons in a mixed Sb(5s)/Bi(6s) crystal-environment. Density functional theory is used to calculate the electronic properties of Sb-alloyed-Bi2WO6 and to study the effects of introducing Sb 5s orbitals to the band structure. The band edge positions, partial charge analyses, and band decomposed charge densities of BiSbWO6 are used to explain the observed trends in relative stabilities and band edge shifts. To isolate the role of the mixed lone-pair, we considered WO3 as a control model. We find that local distortions caused by Sb 5s lone-pair electrons lead to upshifts in both valence and conduction band edges.