The Solid Solution Eu1–xSrxAuIn

Abstract

EuAuIn and SrAuIn (TiNiSi type structure, space group Pnma) form a complete solid solution Eu1–xSrxAuIn. Samples with x = 0.2, 0.4, 0.5, 0.6 and 0.8 were prepared by melting of the elements in sealed tantalum ampoules followed by slow cooling. The samples were characterized through Guinier powder patterns. The X‐ray data confirm Vegard type behavior. The crystal structures of Eu0.8Sr0.2AuIn and Eu0.5Sr0.5Au1.02In0.98 were refined from single‐crystal X‐ray diffraction data in order to confirm the Eu/Sr site occupancies. Temperature‐dependent magnetic susceptibility data confirm divalent europium. The Néel temperature linearly drops from 21.0 K for EuAuIn and long‐range magnetic ordering is still present in the x = 0.8 sample with TN = 4.1 K. Low‐field measurements indicate two successive magnetic ordering temperatures for all samples, resulting from a complex interplay of antiferromagnetic and ferromagnetic interactions, similar to the tetrelides EuMgX (X = Si, Ge, Sn). 151Eu Mössbauer spectra confirm the divalent ground state and show complex magnetic hyperfine field splitting at 6 K.