Heat capacity study of relaxor PbMg1/3Nb2/3O3 in a wide temperature range

Giant electrocaloric effect in the thin film relaxor ferroelectric 0.9PbMg1∕3Nb2∕3O3–0.1PbTiO3 near room temperature

“…In the temperature range of interest, the heat capacity C = 120 J mol −1 K −1 remains sensibly constant or even decreases at low temperatures. 12 We note that assuming a constant value of C despite an ϳ50% peak 11 resulted in excellent agreement with direct EC measurements of ⌬T in bulk 11 We assume the bulk value of = 8.08 g cm −3 . 13 EC temperature changes obtained with ͑1͒ are presented in Fig.…”

Specific heat of a PIN-PMN-PT single-crystal up to 500K

“…The temperature of the hump is about the temperature of the diffused phase transition obtained by our preliminary dielectric data, and also reported in literature in the similar PIN-PMN-PT compound (24/42/34) 454-469 K. 22 One should also note the apparent presence of deviations in behavior of the background specific heat below 100 K for PMN and 200 K for PIN-PMN-PT, which is in accordance with the previous works on specific heat of PMN. [8][9][10][11] Calculation of the background specific heat at these temperatures demands accounting of the consideration stated in Ref. 11.…”

“…10 for calculating a linear term in the temperature. As a result we obtained the formula for the background specific heat, which describes well the experimental curves at our disposal:…”

“…[8][9][10] However, using data for higher temperatures it is possible to calculate the background as a combination of Einstein and Debye functions. We suppose that one can draw such functions for our interval of temperatures.…”

Anomalous Behaviour of the Specific Heat of AB′B″O3Complex Perovskites at Low Temperatures

“…However, there is no understanding of the behaviour of specific heat in ferroelectric crystals, which has a certain type of static disorder. At present, there is a renewal of interest in studying the thermodynamic properties of such crystals [5][6][7].…”