Antimony oxofluorides – a synthesis concept that yields phase pure samples and single crystals

Abstract

The single crystals of the new isostructural compounds Sb₃O₄F and Y_0.5Sb_2.5O₄F and the two previously known compounds M-SbOF and α-Sb₃O₂F₅ were successfully grown by a hydrothermal technique at 230 °C. The new compound Sb₃O₄F crystallizes in the monoclinic space group P2₁/c; a = 5.6107(5) Å, b = 4.6847(5) Å, c = 20.2256(18) Å, β = 94.145(8)°, z = 4. The replacing part of Sb with Y means a slight increase in the unit cell dimensions. The compounds M-SbOF and α-Sb₃O₂F₅ have not been grown as single crystals before and it can be concluded that hydrothermal synthesis has proved to be a suitable technique for growing single crystals of antimony oxofluorides because of the relatively low solubility of such compounds compared to other antimony oxohalides that most often have been synthesised at high temperatures by solid state reactions or gas–solid reactions.