Mutual cation substitutions in palmierite orthovanadates: M3(VO4)2–M2Me2/3(VO4)2 systems where M = Sr, Ba, or Pb and Me = La or Bi

详细

We performed the synthesis and studied the extents and compositions of solid solutions (ss) formed by heterovalent substitutions in M₃(VO₄)₂–M₂Me_2/3(VO₄)₂ systems where M = Sr, Ba, or Pb and Me = La or Bi. A continuous solid solution (css) series was shown to be formed only when the initial compounds crystallize in palmierite structure. Bi³⁺ and La³⁺ were shown to occupy different positions (3а and 6с, respectively) in the crystal lattice of Sr₃(VO₄)₂-base ss.