Monte Carlo simulations of high-moment - low-moment transitions in Invar alloys

In: The European Physical Journal B, Jg. 2 (1998) ; Nr. 1, S. 107-119
Zeitschriftenaufsatz / Fach: Physik
We have reproduced magneto-volume effects typical for Invar alloys by examining a spin-analogous model which describes coupled spatial and magnetic degrees of freedom and, additionally, chemical disorder. Constant pressure Monte Carlo simulations of this model show an almost vanishing thermal expansion over a broad range of temperatures below T_C,a softening of the bulk modulus and the absence of a sharp peak in the specific heat at the magnetic phase transition as observed in Fe65Ni35 Invar.