Chemical bonding and electronic states in α-PbO: Analysis by an ab initio band calculation

Abstract

Ab initio band-structure calculations using density-functional theory within the generalized gradient approximation have been performed on α-PbO. The structure optimization of the ground state of α-PbO showed that the calculated lattice parameters and the fractional coordinate of Pb(z) are in good agreement with those of experiments. Partial covalent bonding caused by hybridization of crystal orbitals was seen in the charge density map between Pb and O in the a-a plane. The analysis through an energy diagram of band structures clearly showed that the hybridization of Pb 6s (6p) and O 2p as well as Pb 6s-Pb 6s interaction is the origin of the structure distortion in α-PbO.