Abstract
By means of an AC calorimetry technique the heat capacity has been measured in several SnxGe1-xTe crystals with x ranging from 0.62 to 0.91. The anomalous specific heat near the transition temperature can be separated into two parts. One shows a step-like behaviour; the height of the step becomes larger with decreasing x. The other contribution is a logarithmic critical behaviour; its critical region becomes broader with decreasing x as well. These characteristics might be related to a tricritical point. It has been found that in Sn0.79Ge0.21Te crystals the anomalous specific heat is proportional to the anomalous elastic stiffness.