Atomic and magnetic structure of the heusler alloys Pd2MnGe, Pd2MnSn, Cu2MnIn, and CoMnSb

Abstract

A detailed neutron diffraction study of Pd2MnSn and Cu2MnIn shows that both have the fully ordered L21 type of Heusler alloy structure and are ferromagnetic with 190 and 575 °K as their respective Curie temperatures. Pd2MnGe shows a preferentially disordered L21 structure with 0.98 Pd + 0.02 Mn on the A- and C-sites and 0.96 Mn + 0.04 Pd on the B-sites. The B-site Mn moments are aligned antiparallel to those on the A- and C-sites and its Curie temperature is 260 °K. The alloy CoMnSb has been found to have an incompletely filled L21 structure and is ferromagnetic below 430 °K.