Studies on rare-earth carboxylates. II. Crystal chemical data on Ln(CH₃CHCH₃COO)₃ where Ln=Er, Tm or Yb

The rare-earth isobutyrates, Ln(CH₃CHCH₃COO)₃ (where Ln = Er, Tm or Yb), have been synthesized and studied crystallographically. The salts are orthorhombic with space group Pmma containing four molecules per unit cell. The lattice parameters are: for Er(CH₃CHCH₃COO)₃, a = 11.35(1), b = 9.806(6), c = 15.40(2) Å, V = 1714 Å³ D^m = 1.67, D_x = 1.66 Mg m^-3; for Tm(CH₃CHCH₃COO)₃, a = 11.32(1), b = 9.781(9), c = 15.39(2) Å, V = 1703 Å³, D_m = 1.68, D_x = 1.68 Mg m^-3; for Yb(CH₃CHCH₃COO)₃, a = 11.23(2), b = 9.665(22), c = 15.34(5) Å, V = 1665 Å³, D_m = 1.68, D_x = 1.73 Mg  m^-3. The JCPDS Diffraction File No for Tm(CH₃CHCH₃CO₂)₃ is 34-1997.