Crystal structure of guanidinium hexafluorido-vanadate(lll), (CN_3H_6)_3[VF_6]: an unusual hybrid compound related to perovskite

摘要

Vanadium fluorides with novel crystal-chemical features and interesting physical properties can be prepared by solvothermal synthetic routes. The title compound, guanidinium hexafluoridovanadate(III), has a cubic structure (space group Pa3), exhibiting isolated regular VF_6 octahedral units, which are hydrogen bonded to protonated guanidinium moieties. Although the VF_6 octahedral units are not linked directly together, there are structural similarities between this crystal structure and those of the wider family of perovskite materials, in particular, hybrid perovskites based on extended ligands such as cyanide. In this context, the octahedral tilt system of the present compound is of interest and demonstrates that unusual tilt systems can be mediated via 'molecular' linkers which allow only supramolecular rather than covalent interactions.