Physical Realization of the Order Parameters at a Microscopic Level of Description

摘要: The phase transition from the initial of crystal gives rise to a state which at microscopic level may be specified by occurrence some spontaneous property on each atom. This is described scalar, vector or tensor. Thus, for example, static magnetic moment arises atom in and therefore an appropriate pseudovector. In case structural displacement (displacive transition) it possible assign dissymmetric polar with respect its position symmetric phase; assignment wholly characterizes this phase. If ordering accompanied distortions, two vectors should phase: pseudovector atomic vector. It better such situation ascribe tensor rank two. For ordering-type characterized scalar quantity that represents relative probability occupying determinate positions crystal.