High-moment - low-moment description of magnetovolume effects in Y(MnxAl1-x)2 and YxSc1-xAl2

In: Phase Transitions, Jg. 75 (2002) ; 1 & 2, S. 221 - 230
Zeitschriftenaufsatz / Fach: Physik
Based on the assumption of a high-moment-low-moment instability of the Mn atom, we construct a simple spin model with coupled magnetic and spatial degrees of freedom to describe the Laves phase systems Y(MnxAl1-x)2 and YxSc1-xMn2. Monte Carlo simulations of this model qualitatively reproduce anomalies observed in these materials like a discontinuous giant volume change and anomalous thermal expansion behavior.