R14(Au, M)51 (R = Y, La–Nd, Sm–Tb, Ho, Er, Yb, Lu; M = Al, Ga, Ge, In, Sn, Sb, Bi): Stability Ranges and Site Preference in the Gd14Ag51 Structure Type

Abstract

Gold is well known for its flexibility in chemical bonding and formation of notable structural features, which finds its origin in the strong relativistic influence on its 5d and 6s valence orbitals. This renders gold an exciting component in the exploration of new intermetallic compounds. Substitution of gold by a post transition metal M may allow the stabilization of ternary compounds where certain binary compounds have not been reported. Twenty new ternary representatives of the Gd14Ag51 structure type have been synthesized within the R-Au-M family (R = Y, La-Nd, Sm-Tb, Ho, Er, Yb, Lu; M = Al, Ga, Ge, In, Sn, Sb, Bi) using solid state synthesis techniques. The list of post transition metals (M) involved in the formation of this type of structure could be augmented by five new representatives. All compounds crystallize in the hexagonal space group P/6m (#175) with the unit cell ranges of a = 12.3136(2) - 12.918(1) A and c = 8.9967(3) - 9.385(1) A, and incorporate different degrees of Au/M mixing. The in...