Metamagnetic transition in Mg(Co,Ni)2 with the hexagonal C14-type Laves phase structure

A magnetic field-induced metamagnetic transition from the paramagnetic state to the ferromagnetic one is predicted to take place in Mg(Co1-xNix)2 with the hexagonal C14-type Laves phase structure, by performing first-principle band structure calculations. It is shown that the system becomes paramagnetic at x⩾0.21 and shows a metamagnetic transition associated with a magnetization jump of about 1μB per 3d transition-metal atom.