Influence of the Increasing Size of the M 2+ Cation on the Crystal Structures of XeF 5 M(SbF 6 ) 3 (M = Ni, Mg, Cu, Zn, Co, Mn, Pd) and (XeF 5 ) 3 [Hg(HF)] 2 (SbF 6 ) 7

The reactions between XeF 5 SbF 6 and M(SbF 6 ) 2 (M 2+ = Ni, Mg, Zn, Co, Mn, Pd) in anhydrous HF (aHF) in a 1:1 molar ratio yielded XeF 5 M(SbF 6 ) 3 upon crystallization. All six structures were characterized at 150 K by single‐crystal X‐ray diffraction. For Mn, there is a phase transition at around 235 K, and for Pd between 260 and 296 K. Similar attempts to prepare new [XeF 5 ] + /M 2+ mixed‐cation salts with M 2+ = Ca, Sr, Ba, Cr, Fe, Ag, Cd, and Hg were only successful for Hg, for which (XeF 5 ) 3 [Hg(HF)] 2 (SbF 6 ) 7 was obtained. The crystal structures of XeF 5 M(SbF 6 ) 3 (M 2+ = Mg, Co, Ni, Zn) and the low‐temperature phase α‐XeF 5 Mn(SbF 6 ) 3 are isotypic with the known XeF 5 Cu(SbF 6 ) 3 . The main features of the crystal structures of β‐XeF 5 Mn(SbF 6 ) 3 and β‐XeF 5 Pd(SbF 6 ) 3 are similar to those of the other XeF 5 M(SbF 6 ) 3 compounds, that is, a 3D framework consisting of rings of MF 6 octahedra that share the apexes with SbF 6 octahedra, forming cavities within which the [XeF 5 ] + cations are located. At 296 K, the disordered [XeF 5 ] + cations in β‐XeF 5 Pd(SbF 6 ) 3 are ordered in the α‐phase (260 K). The crystal structure of (XeF 5 ) 3 [Hg(HF)] 2 (SbF 6 ) 7 consists of columns of [Hg(HF)] 2+ cations bridged by SbF 6 units. The charge balance is maintained by the [XeF 5 ] + cations, which form secondary contacts with the F atoms of the SbF 6 groups.