Physical properties of EuPtIn4 intermetallic antiferromagnet

We report the physical properties of EuPtIn4 single crystalline platelets grown by the In flux technique. This compound crystallizes in the orthorhombic Cmcm structure with lattice parameters a = 4.542(1) <(A)over dot>, b = 16.955(2) <(A)over dot> and c = 7.389(1) <(A) over dot>. Measurements of magnetic susceptibility, heat capacity, electrical resistivity, and electron spin resonance (ESR) reveal that EuPtIn4 is a metallic Curie-Weiss paramagnet at high temperatures with an effective moment of mu(eff) approximate to 7.8(1) mu(B) due to divalent Eu ions. At low temperatures, antiferromagnetic (AFM) ordering is observed at T-N = 13.3 K followed by a successive anomaly at T* = 12.6 K. In addition, within the magnetic state, a spin-flop transition is observed with H-c similar to 2.5 T at T = 1.8 K when the magnetic held is applied along the ac-plane. In the paramagnetic state, a single divalent Eu2+ Dysonian ESR line with a Korringa relaxation rate of b = 4.1(2) Oe/K is observed. Interestingly, even at high temperatures, both ESR linewidth and electrical resistivity reveal a similar anisotropy. We discuss a possible common microscopic origin for the observed anisotropy in these physical quantities likely associated with an anisotropic magnetic interaction between Eu2+ 4f electrons mediated by conduction electrons. (C) 2014 Elsevier B.V. All rights reserved.