Nelson W L, Jayasinghe A S, Graf D, Latturner S, Baumbach R E
National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, United States of America.
Department of Physics, Florida State University, Tallahassee, FL 32306, United States of America.
J Phys Condens Matter. 2020 May 11;32(31). doi: 10.1088/1361-648X/ab849c.
X-ray diffraction, magnetic susceptibility, magnetization, heat capacity and electrical resistivity results are reported for single crystals of two structural variants of EuNiSbthat crystallize in the CaBeGeand ThCrSi-type structures. While the former occurs with a stoichiometric ratio, the latter exhibits a Ni site vacancy (= 0.36). Both systems exhibit similar magnetic behavior at elevated temperatures, where there is an isotropic Curie-Weiss temperature dependence that indicates an antiferromagnetic exchange interaction between divalent europium ions, although it is stronger for the CaBeGe-variant. At low temperatures, the differing structural environments that surround the Eu ions result in distinct ordering behavior. The CaBeGe-variant orders antiferromagnetically near= 6.9 K and then undergoes a first order phase transition at= 4.6 K. The ThCrSi-variant exhibits simpler behavior, with antiferromagnetic ordering at= 5.6 K. For both compounds, an applied magnetic field suppresses the ordering temperatures and induce metamagnetic phase transitions, while applied pressure causes the ordering temperatures to increase. From these results, EuNiSbemerges as a useful system in which to study the impact of structural variation on magnetism in a Eu-based metal.
