Formation of nano-amorphous domains in Ce75Al25 - XGax alloys with delocalization of cerium 4f electrons

Abstract

The formation of nano-amorphous domains in melt spun ribbons of Ce75Al25 - xGax alloys with x = 0, 0.01, 0.1, 0.5 and 1 is reported. For x = 0, a homogenous metallic glass feature is observed. Ga substitution has led to phase separation giving rise to nano-amorphous domains in a glassy matrix. The rationale of phase separation could not be explained in terms of enthalpy of mixing of the three possible binaries in this system. The Ce L3-edge XAS spectra of melt-spun ribbons for x = 0, 0.5 and 4 have shown appearance of 4f0 delocalized states in Ga substituted alloy. Such a substitution has led to shortening of Ce-Ce distance in the alloys owing to chemical pressure. This work, therefore, opens up new direction of research for delineating issues pertaining to phase separation in amorphous systems. © 2015 Elsevier Ltd. All rights reserved.