Specific heat of Co2+, Fe2+and Mn2+perchlorates at low temperature

Abstract
The temperature dependence of the specific heat of Co2+, Fe2+ and Mn2+ perchlorates have been studied using a heat-pulse technique. It is found that all three compounds have a lambda -shaped Cp against T dependence around the transition point. In addition it is shown from the analysis of the critical region data that the phase transition has a second-order origin.