A 119Sn and 151Eu Mössbauer spectroscopic, magnetic susceptibility, and electrical conductivity investigation of the stannides EuTSn (T = Cu, Pd, Ag, Pt)

Abstract

The title compounds were prepared from the elements by reaction in sealed tantalum tubes in a high frequency furnace. EuCuSn and EuAgSn crystallize with the KHg2 type structure with a statistical distribution of the copper (silver) and tin atoms on the mercury position. EuPdSn and EuPtSn adopt the TiNiSi type structure, a ternary ordered version of KHg2. The four stannides show Curie–Weiss behaviour above 60 K with experimental magnetic moments between 7.75(5) and 8.10(5) µB/Eu indicating divalent europium. While EuCuSn remains paramagnetic down to 4.2 K, antiferromagnetic ordering is observed for EuAgSn, EuPdSn and EuPtSn with Néel temperatures of 6.0(5), 15.5(5) and 28.5(5) K, respectively. EuPdSn and EuPtSn show metamagnetic transitions at fields of 2.5(2) and 0.8(1) T, respectively. The stannides EuCuSn, EuPdSn, EuAgSn and EuPtSn are metallic conductors. Temperature dependent 151Eu and 119Sn Mössbauer spectroscopic data confirm the magnetic transition temperatures and yield values of the internal (and transferred) magnetic flux densities. A compilation of the 151Eu isomer shifts for the whole series of EuTX (T = transition metal; X = element of the 3rd, 4th or 5th main group) compounds reveals an interesting linear correlation with the electron count.