Crystal structures of phases observed in [H3O]+/M2+/[SbF6]− system (M = Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, Pd, Cd)

Abstract

The reactions between the MO (M=Be, Mg, Ca, Sr, Ti, V, Nb, Mn, Ni, Cu, Pd, Zn, Hg, Sn, Pb) and SbF5 in liquid aHF were investigated. Reactions with the MO (M=Mg, Ni, Cu and Zn) yielded H3OM(SbF6)3 compounds. Both BeO and PdO didn’t show any sign of reactivity meanwhile MO (M=V, Nb, Ti) gave products with M in oxidation state higher than two. The rest of the MO (M=Ca, Sr, Mn, Hg, Sn, Pb) formed mixtures of M(SbF6)2, H3OSbF6 and/or H3OSb2F11. Reactions between H3OSbF6 and M(SbF6)2 (M=Fe, Co, Ni) also gave H3OM(SbF6)3 compounds, meanwhile similar attempts with H3OSbF6 and M(SbF6)2 (M=Ca, Mn, Pd, Ag, Cd, Sn) to prepare [H3O]+/M2+/[SbF6]− salts failled. However, slow crystallizations of H3OSbF6 and M(SbF6)2 (M=Mn, Pd, Cd) mixtures resulted in the single crystal growth of new (H3O)3M(SbF6)5 phases which crystal structures are not isotypic. Similar procedure with H3OSbF6/Cr(SbF6)2 mixture resulted in few light orange crystals of (H3O)3[CrIV(SbF6)6](Sb2F11)·HF. Its crystal structure determination showed the presence of discrete [CrIV(SbF6)6]2− units where each of Cr atoms is found in a homoleptic coordination of six SbF6 groups.