Heat capacity studies of phase transitions in K3Nb3O6(BO3)2

Heat capacity measurements of K3Nb3O6(BO3)2, a borate that exhibits superionic conductivity and ferroelectric properties, have been performed in the 60–220 K temperature range. In this work, the presence of two heat capacity anomalies has been documented. The first anomaly occurs at 198.3 K and it has been attributed to a first-order phase transition. The second anomaly suggests presence of second-order phase transition at around 80 K.