ScAuIn – a new representative of the RAuIn series

Abstract

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 ∼6 ​× ​10−5 emu/mol. The Sommerfeld coefficient γ 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 at the Fermi level N(EF). 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.