Mossbauer effects and magnetic properties of mixed valent europium sulfide, EuPd3S4

EuPd3S4 with a NaPt3O4-type structure was investigated by X-ray diffraction , (EU)-E-151 Mossbauer spectroscopy, magnetic susceptibility, and specific heat measurements, In this compound, Eu2+ and Eu3+ ions exist in the ratio of ca. 1:1. The Debye temperatures of Eu2+ and EU3+ were determined to be 1 95 and 220 K, respectively, The isomer shift of Eu2+ in this EuPd3S4 at 300 K is largest among EU2+ sulfides because of the compression effect of the EU2+ sites. The temperature dependence of the isomer shifts suggests that a hopping of the electron between EU2+ and Eu3+ occurs in EuPd3S4. The EU2ion was found to be in the antiferromagnetic state below 3 K from both the magnetic susceptibility and specific heat measurements. (C) 2001 Academic P ress.