Disordering of the [NbOF(5)](2-) complex anions in bis(glycinium) pentafluoridooxidoniobate(V) and bis(beta-alaninium) pentafluoridooxidoniobate(V) dihydrate

作者：Gerasimenko A V^*; Pushilin M A; Davidovich R L

来源：Acta Crystallographica Section C-Crystal Structure Communications, 2008, 64: M358-M361.

DOI：10.1107/S0108270108026413

The title compounds, (C(2)H(6)NO(2))(2)[NbOF(5)], (I), and (C(3)H(8)NO(2))(2)[NbOF(5)]center dot 2H(2)O, (II), are built from isolated distorted octahedral [NbOF(5)](2-) complex anions, amino acid cations and water molecules [for (II)]. In the pentafluoridooxidoniobate(V) anions, the Nb and O atoms, and the F atoms in trans positions with respect to the O atoms, are disordered about an inversion centre for both structures. The Nb atoms are shifted from the inversion centres by distances of 0.1455 (1) and 0.1263 (2) angstrom for (I) and (II), respectively. The Nb=O and Nb-F(trans) bond lengths are 1.7952 (3) and 2.0862 (3) angstrom, respectively, for (I), and 1.8037 (7) and 2.0556 (7) angstrom for (II). In the crystal structures, cations and water molecules [for (II)] are linked to the [NbOF(5)](2-) anions via hydrogen bonds. This study demonstrates the possibility of true geometry determination of disordered [NbOF(5)](2-) complex anions in centrosymmetric structures.

• 出版日期2008-11