Evidence for atomic disorder inB8-structure Mn-Sn by mechanical milling

Mechanical milling of ferrimagnetic B8-structure Mn1.5Sn results in a decrease of the magnetization at 4.2 K in a field of 21 T. This is in contrast to a number of other ferromagnetic B8-structure compounds, where the magnetization increases. The explanation is given in terms of a redistribution of transition-metal atoms over two different types of transition-metal sites. The Curie temperature (TC) of the compound also decreases. The unit-cell volume increases with milling time, which provides additional evidence for the particular type of atomic disorder. The material remains in its original crystal structure even after prolonged periods of ball milling.