Structural peculiarities of (PbMg1/3Nb2/3O3)(1-x)-(PbTiO3)(x) solid solutions

The results of X-ray high-temperature study of (PbMg1/3Nb2/3O3)(1-x)-(PbTiO 3)(x) (x=0.06; 0.1; 0.4) are presented. The structure refinement is perform ed and the results of the refinement are used to calculate the probability density function rho(sigma). It is demonstrated that at x=0.06 and x=0.1 th e center of gravity of rho(sigma) for the lead ions is shifted from the ide al (000) position, while at x=0.4 the bell-shaped distribution has the maxi mum at sigma=0. The disappearance of the shifts of lead ions at x=0.4 is co nsidered as an evidence of the suppression of the local electric and elasti c fields essential for the relaxer phenomena.