Calorimetric study and Landau analysis of the phase transitions in PbZr1-xSnxO3 single crystals with 0≤x≤0.4

Differential scanning calorimetry experiments have been performed for PbZr1-xSnxO3 single crystals where 0≤x≤0.4 at the temperature range of 100-600 K. The temperatures and orders of particular phase transitions have been determined and the phase diagram was compared to dielectric measurements. The first order character of the phase transitions in PbZr1-xSnxO3 was discussed. The total transitions energy and entropy at the phase transitions were calculated. The excess specific heat and excess entropy associated with the phase transitions were analysed using Landau theory. The comparison of calorimetric data with the evolution of the order parameter indicates that the phase transitions in PbZr1-xSnxO3 single crystals seem to follow a mean field Landau potential. The results are compared to the earlier dielectric and birefringence experiments. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)