The formation of the magnetic moment of Co atom in pseudobinary alloys CoTi_1-xAl_xin relation to a Heusler alloy Co₂TiAl

Abstract

The formation of the magnetic moment of the Co atom is investigated in the pseudobinary alloys CoTi1-xAlx by X-ray diffraction, magnetic measurement and NMR of 59Co. Magnetization and Curie temperature have a maximum at the composition less than x=0.5, where the alloy becomes one of the well known ferromagnetic Heusler alloys. The results are discussed on the basis of a local environment model. The moment of the Co atom appears when the atom is surrounded with four, five and six Ti atoms at nearest-neighbour distance.