The crystal structures of tritin(II) bromide pentafluoride and ditin(II) chloride trifluoride

Abstract

The crystal structures of the title compounds have been determined from X-ray photographic data by Patterson and Fourier methods. The crystals of both compounds have pseudo-high-symmetry cells but Sn₃BrF₅ is monoclinic with space group P2₁/n and Z= 4 in a unit cell of dimensions a= 4.27, b= 12.70, c= 12.70 Å, β= 90.0°, and Sn₂ClF₃ is orthorhombic with space group P2₁2₁2₁ and Z= 4 in a unit cell of dimensions a=b=c= 7.88 Å. Both structures contain infinite tin–fluorine cationic networks in which all the tin atoms have a trigonal pyramidal co-ordination of nearest-neighbour fluorine atoms. The shortest Sn–Br (3.29 Å) and Sn–Cl (3.14 Å) distances are consistent with the presence of free Br^– and Cl^– ions in the lattices.