Key points are not available for this paper at this time.
An n-component substitutional solid solution in a perfect crystal can be characterized uniquely by n−1 independent composition functions. There are n (n−1) /2 distinct short-range-order parameters αij (i, j = 1, 2,. . . n−1) corresponding to these (n−1) independent compositions. The SRO parameters are linearly but not quadratically independent: for example, in ternary systems, the following equation holds Σ (1 − c₁) (1 − c2) α11α22 − c1 c2α12α21 = 0 in which c1 and c2 are the average compositions pertaining to atomic species 1 and 2, the summation extending over all significant correlation ranges in the crystal. This relation can be used to reduce the uncertainty relative to the interpretation of diffraction experiments realized with less than the optimum number of radiations.
D. de Fontaine (1971) studied this question.