Crystal data for 14 fluorides LnMoF₇ (Ln=lanthanide)

Ternary fluorides LnMoF₇ have been synthesized by solid-state reactions between MoF₄ and LnF₃ for yttrium and all lanthanides except dysprosium. These compounds are all monoclinic, space group P2₁; they are isotypic with the LnZrF₇ and LnNbF₇ compounds. Unit-cell parameters for the 14 compounds are: LaMoF₇: a = 6.3952(4), b = 5.6285(4), c = 8.4351(5) Å, β = 102.695(6)°, V = 296.2(5) ų, Z = 2, D_x = 4.12 Mg m⁻³; CeMoF₇: a = 6.3275(5), b = 5.6657(5), c = 8.4122(7) Å, β = 102.985(7)°, V = 293.9(5) ų, Z = 2, D_x = 4.17 Mg m⁻³; PrMoF₇: a = 6.3155(5), b = 5.6599(7), c = 8.4167(6) Å, β = 102.946(6)°, V = 293.2(5) ų, Z = 2, D_x = 4.19 Mg m⁻³; NdMoF₇: a = 6.1152(4), b = 5.6983(4), c = 8.2914(5) Å, β = 103.201(6)°, V = 281.3(5) ų, Z = 2, D_x = 4.41 Mg m⁻³; SmMoF₇: a = 6.0686(4), b = 5.6503(6), c = 8.2261(5) Å, β = 103.246(5)°, V = 274.6(4) ų, Z = 2, D_x = 4.59 Mg m⁻³; EuMoF₇: a = 6.0337(5), b = 5.6311(4), c = 8.1953(5) Å, β = 103.420(6)°, V = 270.8(4) ų, Z = 2, D_m = 4.63, D_x = 4.67 Mg m⁻³; GdMoF₇: a = 6.0138(4), b = 5.6241(5), c = 8.1726(5) Å, β = 103.371 (7)°, V = 268.9(5) ų, Z = 2, D_x = 4.77 Mg m⁻³; TbMoF₇: a = 6.0081(5), b = 5.6621(5), c = 8.1868(5) Å, β = 103.685(7)°, V = 270.6(5) ų, Z = 2, D_x = 4.76 Mg m⁻³; HoMoF₇: a = 5.9801(4), b = 5.6456(5), c = 8.1282(5) Å, β = 103.465(6)°, V = 266.9(4) ų, Z = 2, D_x = 4.90 Mg m⁻³; ErMoF₇: a = 5.9293(5), b = 5.5732(5), c = 8.0831(5) Å, β = 103.540(7)°, V = 259.7(5) ų, Z = 2, D_m = 5.01, D_x = 5.07 Mg m⁻³; TmMoF₇: a = 5.9309(4), b = 5.5976(5), c = 8.1096(4) Å, β = 104.056(5)°, V = 261.2(4) ų, Z = 2, D_x = 5.06 Mg  m⁻³; YbMoF₇: a = 5.8950(4), b = 5.5448(4), c = 8.0199(5) Å, β = 103.552(6)°, V = 254.9(4) ų, Z = 2, D_x = 5.24 Mg m⁻³; LuMoF₇: a = 5.8593(5), b = 5.5172(5), c = 8.0423(6) Å, β = 103.752(8)°, V = 252.5(6) ų, Z = 2, D_x = 5.31 Mg m₋₃; YMoF₇: a = 5.9397(4), b = 5.5945(5), c = 8.1108(5) Å, β = 103.643(6), V = 262.0(4) ų, Z = 2, D_x = 4.03 Mg m⁻³. The variation of unit-cell data is in agreement with the lanthanidic contraction and the tetrad effect. Powder diffraction data have been obtained at 293 K with a Philips PW1050/25 counter diffractometer; Ni-filtered Cu Kα radiation ( = 1.5418 Å). The JCPDS Diffraction File Nos. are: LaMoF₇ 38–1498; CeMoF₇ 38–1497; PrMoF₇ 38–1496; NdMoF₇ 38–1495; SmMoF₇ 38–1494; EuMoF₇ 38–1493; GdMoF₇ 38–1492; TbMoF₇ 38–1491; HoMoF₇ 38–1490; ErMoF₇ 38–1489; TmMoF₇ 38–1488; YbMoF₇ 38–1487; LuMoF₇ 38–1486; YMoF₇ 38–1485.