An X-ray crystallographic study of [Xe2F3][SbF6] and dimorphism in [Xe2F3][AsF6]; and a density functional theory study of the Xe2F3+ cation

The Xe2F3+ cation has been studied by X-ray crystallography with AsF6− and SbF6− as counter anions. The [Xe2F3][AsF6] salt was found to be dimorphic with a monoclinic phase: C2/c, a=25.756(3)Å, b=8.556(1)Å, c=15.356(2)Å, β=126.592(5)°, V=2716.9(6)Å3, Z=12 and R1=0.0389 at −127°C; and a trigonal phase: P3221, a=8.602(5)Å, c=10.665(9)Å, V=683.4(8)Å3, Z=3 and R1=0.0385 at −116°C. The [Xe2F3][SbF6] salt crystallizes in the monoclinic system: C/c, …