Structural properties of near-stoichiometric composition of Ba(B′1/3B″2/3)O3 (B′ = Mg, Co, or Zn and B″ = Nb or Ta) perovskites

Near-stoichiometric compositions of Ba(B′1/3B″2/3)O3 (B′ = Mg, Co, or Zn and B″ = Nb or Ta) perovskite-type materials with nonstoichiometry on Ba and B′ positions were studied by room temperature Raman spectroscopy and transmission electron microscopy. The studied materials with 1:2 ratio of B-site cations belong to the family of perovskites that has tolerance factor larger than unity, indicating formation of a strained structure. This family …