ScAuIn - a new representative of the RAuIn series

A new representative of the RAuIn series was discovered in the Sc-Au-In system. ScAuIn crystallizes in the hexagonal HfRhSn-type structure (space group P-62c) with a = 0.75667(2), c = 0.71873(2) nm). Magnetization measurements revealed that ScAuIn is a Pauli paramagnet with magnetic susceptibility of similar to 6 x 10(-5) emu/mol. The Sommerfeld coefficient gamma of 2.8 mJ K-2 mol(-1) derived from the specific heat measurements is comparable with those obtained from the modeled density of states a the Fermi level N(E-F). Ab initio calculations predict metallic conductivity and show strong chemical bonding within the [InAu] sublattice. The structural stability of the RAuIn with ZrNiAl and HfRhSn structure types is discussed based on crystal chemistry analysis and DFT modeling.