Valence behavior of Eu-ions in intermetallic compound Ce_(0.5)Eu_(0.5)Pd_3B_(0.5)

摘要

We have studied the valence behavior of rare-earth ions, in particular Eu-ions, in a cubic intermetallic compound Ce_(0.5)Eu_(0.5)Pd_3B_(0.5) which is a homogeneous solid solution of two mixed-valent compounds CePd_3 and EuPd_3B. Results of ~(151)Eu Mossbauer spectroscopic measurements show that two different valence states, i.e., divalent- and trivalent-like states of Eu-ions exist in the compound. The possible reason for the observed heterogeneous valency vis-d-vis the variation in the chemical environment and the number of nearest-neighbor B atoms surrounding the Eu-ions has been discussed. Our results demonstrate that B incorporation in such Eu-based cubic intermetallic compounds leads to a situation where heterogeneous-valence state of Eu-ions is an energetically favorable ground state.