Structural diversity in hybrid vanadium(IV) oxyfluorides based on a common building block

Abstract

There are only limited reports on vanadium(IV) oxyfluorides (VOFs) with extended crystal structures. Here we expand and enrich the list of existing VOFs with a series of 14 new materials "VOF-n (n = 1-14)" prepared using ionothermal and solvothermal synthesis methods. All of these materials arise from the condensation of a dimeric structural motif. These VOFs can be classified into three groups depending on their key structural features; layer structures: VOF-1 "[HN2C7H6][V2O2F5]", VOF-2 "[HN2C4H4][V2O2F5]", VOF-3 "[HN2C3H4][V2O2F5]" and VOF-4 "V-2(N2C4H4)O2F4", ladder like structures: VOF-5 "[NH4(HN2C3H4)][V2O2F6]", VOF-6 "[K(HN2C3H4)][V2O2F6]", VOF-7 "[HNH2CH2CH3][VOF3]", VOF-8 "[HN2C7H6][VOF3]", VOF-9 "[H2N2C4H6][V2O2F6]", VOF-10 "beta-RbVOF3", VOF-11 "alpha-KVOF3", VOF-12 "beta-KVOF3", VOF-13 "[H-2(NH2)(2)(CH2)(2)][V2O2F6]", and a chain structure: VOF-14 "[H2N2C6H12][V2O2F7]". The crystal structures of VOF-n are presented, and their synthetic and structural relationships are discussed.