Predicting the stability and electronic structure of alkali metal aurides.

Density functional theory calculations of phonon modes predict that some compounds of the alkali metal aurides family, general formulaAu(= K, Rb or Cs;= Ti, Zr, Hf, Sn or Pb), have stable three-dimensional phase with a double perovskite-type structure and cubic3¯space group (KPtCl-type). Bader's charge analysis shows that most electron density is located within the six atoms at the octahedra vertices like double perovskite halides. However, the short spacing between Au anions enables d-orbital interactions between them.