The Crystal Structure of Caesium Oxotetrafluorovanadate(V)

Abstract

The crystal structure of caesium oxotetrafluorovanadate(V) has been solved and refined to an R-value of 0.070 using diffractometer measurements. The cell dimensions are: a = 548.4(2) pm, b = 634.2(2) pm, c = 1403.4(3) pm. The space group is Pnma (No. 62) with four formula units per cell. Each vanadium atom lies 32.6 pm above the base of a tetragonal pyramid with oxygen at the apex (V=O length = 152.9 pm) and fluorine at the four base corners (mean V—F length = 178.8 pm). The tetragonal pyramids are linked by cis-fluorine bridges involving a long V—F bond (V—F(2 1 ) = 231.2 pm) to give an anionic chain structure. Structural relationships with other fluorides and oxide-fluorides are noted, and the bond lengths are discussed.