155Gd Mössbauer effect and magnetic properties of ternary rare earth compounds of the type RT 2Ge 2 (T3d, 4d)

Abstract

We investigated the magnetic properties and the 155Gd Mössbauer spectra of rare earth ternaries of the type RT 2Ge 2 (T3d, 4d). The electric field gradient V zz derived from the quadrupole splitting of the Mössbauer spectra gives rise to a sign change when passing across the 3d and 4d series. This behaviour was explained in terms of decreasing hybridization between the Gd valence electron states and the d electron states of the T atoms, as already reported previously for the corresponding silicides. The sign of V zz was shown to be strongly correlated with the macroscopic magnetic anisotropy behaviour of the series of compounds RT 2Ge 2.