Concentration Fluctuations and the Heat Capacity of Fe–Cr Alloys

Abstract

The low temperature heat capacity of Fe–Cr alloys becomes anomalously large close to the critical concentration for ferromagnetism at 0 K (C. H. Cheng, C. T. Wei and P. A. Beck: Phys. Rev. 120 (1960) 426): An anomaly persists up to high temperatures at the same composition (K. Shröder: Phys. Rev. 125 (1962) 1209) and this has led to the suggestion that the whole of the low temperature anomaly is due to a high density of states of the itinerant electrons and is not ferromagnetic in origin.
Using a model of the alloy in which concentration fluctuations are present it is shown that the low temperature anomaly may be accounted for in terms of a ferromagnetic transition.