The Wavelet-Analysis at Monte-Carlo Modeling of Phase Transitions in a Ferroelastic Crystal of Lithium Ammonium Sulphate

Using methods of the wavelet-analysis at Monte-Carlo modeling a behavior of thermodynamic parameters of Ising model for the ferroelectric-ferroelastic crystal of lithium ammonium sulphate LiNH(4)SO(4) is studied. The discussed method is similar to Monte-Carlo Renormalization Group (MCRG), but it is more effective, thanks to a presence of algorithm of fast wavelet-transformation (WT). The short review of the wavelet transform and Monte-Carlo modeling by means of MCRG algorithm has been made. Temperature dependences of a specific heat capacity and dielectric permittivity for a set of lattice models with the sizes N x N at N = 64, 128, and 256 were derived as a result of 1, 2, 3-level WT. Critical exponents are found by numerical differentiation of a temperature dependence of thermodynamic parameters near a temperature of phase transition.