Pressure dependence of the magnetisation of YFe2and ZrFe2: computation and experiment

Values of delta ln sigma / delta P, where sigma is the magnetisation per unit mass, for YFe2 (ZrFe2) of -8.4+or-0.4 (-6.3+or-0.3)*10-4 kbar-1 were obtained from forced magnetostriction measurements on polycrystalline samples at 4.2K in fields of up to 12 T. These values are shown to be in reasonable agreement with ab initio computer calculations of delta ln sigma / delta P but contradict earlier experimental work. The agreement between experiment and theory for delta ln sigma / delta P provides further evidence that YFe2 and ZrFe2 are ferrimagnetic.