부산대학교 도서관

Abstract: Ab-initio molecular dynamics (MD) study of oxygen ion diffusion in the oxide ion conducting solid electrolyte δ-Bi3YO6 is presented. Vacancy ordering models were tested by structure relaxation and that for <111> vacancy pairs was found to have the highest total energy per atom, while those for <110>, <100> and random vacancy distributions were found to have similar energies. Evidence for polarization of bismuth charge density is seen for <100> and <110> vacancy pair configurations, consistent with stereochemical activity of the Bi 6s 2 lone pair. MD studies of oxygen diffusion were carried out at three temperatures. Vacancy pair alignments during these simulations were predominantly in the <110> direction, consistent with previous neutron total scattering results. [Copyright &y& Elsevier]