The effect of such random fields upon the order that was induced by impurity dipoles was studied theoretically for the case of strongly polarizable insulators. Point electric charges and elastic dipoles (dilatation centers) were taken to be examples of additional defects. A distribution function which took account of the simultaneous effect of the random fields of both dipoles and additional defects was developed. This function was used to calculate the phase-transition temperature and the critical concentration of dipoles which were necessary for the occurrence of long-range order at absolute zero. It was shown that the additional defects markedly increased the critical concentration of dipoles, and lowered the phase transition temperature, to such an extent as to destroy completely the long-range order.

M.D.Glinchuk, V.A.Stefanovich: Fizika Tverdogo Tela, 1995, 37[1], 139-51 (Physics of the Solid State, 1995, 37[1], 75-80)