Oxygen-deficient barium lead oxide perovskites

Abstract
Through careful selection of reduction conditions it is found that both BaPbO3 and Ba4 Pb3 O10 can be prepared with significant amounts of oxygen deficiency. In both cases, crystallographic unit cells and resistivities change with oxygen content. Hall-effect measurements, however, indicate that the oxygen nonstoichiometry does not change the mobile-carrier concentration, suggesting that the electrons introduced are strongly trapped. The oxygen-deficient materials BaPbO2.90 and Ba4 Pb3 O9.86 are not superconducting down to 70 mK.