Published online by Cambridge University Press: 29 February 2012
[Zr2F8(dmso)2(H2O)2], a dehydration product of [ZrF4(dmso)(H2O)2]⋅2H2O, crystallizes in the orthorhombic symmetry [space group Cmca, a=7.8266(3) Å, b=13.5847(5) Å, c=15.6119(6) Å, and Z=4]. The structure, solved ab initio in direct space from X-ray powder diffraction data, is built up from [Zr2F8O4] bipolyhedra formed by edge sharing of [ZrF5O2] pentagonal bipyramids (condensed from isolated [ZrF4O3] pentagonal bipyramids in the precursor). Difficulties associated with a fortuitous hexagonal pseudosymmetry were surmounted. The dmso departure at 220 °C leads to an amorphous phase.