Redetermination of Na3TaF8

Artikel i vetenskaplig tidskrift, 2010

The crystal structure of trisodium octafluoridotantalate, Na3TaF8, has been redetermined using diffractometer data collected at 153 K, resulting in more accurate bond distances and angles than obtained from a previous structure determination based on film data. The structure is built from layers running along [101], which are formed by distorted [TaF8] antiprisms and [NaF6] rectangular bipyramids sharing edges and corners. The individual layers are separated by eightcoordinated Na ions. Two atoms in the asymmetric unit are in special positions: the Ta atom is on a twofold axis in Wyckoff position 4e and one of the Na ions lies on an inversion centre in Wyckoff site 4d.