What is "tetraxenonogold"

n. (context inorganic compound English) The cation AuXe₄²⁺

Tetraxenonogold(II), gold tetraxenide(II) or AuXe is a cationic complex with a square planar configuration of atoms. It is found in the compound AuXe(SbF), which exists in triclinic and tetragonal crystal modifications. The AuXe ion is stabilised by interactions with the fluoride atoms of the counterion. The Au-Xe bond length is 274 pm.

Tetraxenonogold(II) is unusual in that it is a compound of the notoriously inert atoms xenon and gold. It is also unusual in that it uses xenon as a transition metal ligand, and in that it contains gold in the +2 oxidation state. It can be produced by reduction of AuF in the presence of fluoroantimonic acid and xenon, and crystallised at low temperature. The xenon bonds with the gold(II) ion to make this complex.