Metal–Insulator Transition in Doped Barium Plumbates

Solid solutions in the Ba(Pb1?xSrx)O3?z system were prepared by aliovalent substitution of Pb4+ Sr2+ ions to investigate effect cation stoichiometry on thermal and electrical properties as x was varied between 0 0.4, temperature range 300–523 K. The starting compound, barium plumbate (BaPbO3), has a perovskite structure is known exhibit metallic conductivity due an overlap O2p nonbonding Pb–O sp? antibonding band, which partially filled available electrons. large difference ionic radii introduces significant strain into (Pb/Sr)O6 octahedra structure. Additionally, charged defects are created account different oxidation states ions. Evidence metal insulator transition (MIT) Mott–Hubbard type been observed at critical concentration