CONCENTRATION-DEPENDENCE OF THE NEEL TEMPERATURE OF MN100-XRHX ORDERED ALLOYS

Concentration dependences of the room temperature lattice constant and the Neel temperature of Mn100-xRhx (19 less than or equal to x less t han or equal to 30) ordered alloys were investigated. The room tempera ture lattice constant becomes larger with increasing x. The Neel tempe rature also increases with the increase of x, and the high Neel temper ature is not explained by an exchange interaction as a function of the Mn-Mn distance, but by the number of 3d electrons in the Mn site. Ass ociated with spin fluctuations, the paramagnetic susceptibility increa ses with increasing temperature and shows a tendency to be, saturated. (C) 1998 Elsevier Science S.A. All rights reserved.