Interplay of electronic structure and unusual development in crystal structure of YbAuIn and Yb3AuGe2In3

Abstract

First-principles calculations within the DFT are employed to investigate the relationship between the electronic structure and the unexpected features of the hexagonal cell parameters of YbAuIn and . Calculations indicate that YbAuIn is an intermediate valent system with one Yb 4f state pinned to the Fermi level, while is closer to integer valency with all Yb 4f states occupied. Structural relaxations performed on LaAuIn and LuAuIn analogues reveal that expansion of the c-parameter in is attributable to larger size of the divalent Yb compared with intermediate valent Yb.