Model of Temperature Dependence of Spontaneous Polarization of Thiourea Monocrystal in Phase I

In this paper we present a model of spontaneous polarization appearing in the crystal of thiourea in phase I, constructed on the basis of the molecular field theory, with the use of the Boltzmann statistics. The model employs the potential energy of interaction between two nonpunctual molecular electric dipoles performing reorientations within the constraints specified by the experimentally determined structural data. The temperature dependences of the spontaneous polarization for different values of the hydrostatic pressure and for different gamma-ray doses were obtained. A comparison between theoretical and experimental results permitted calculation of the parameters of the theory presented.