The Calculation of the Cosine Seminvariants
Generally speaking, the implementation of the several formulas for the cosine seminvariants cos φ, cos(φ1 + φ2), and, in the space group P212121, cos 2φ, as given in Chapter II, and their generalizations and analogues in the space groups of higher symmetry, presents few if any serious obstacles. However a few remarks may prove helpful.
KeywordsReciprocal Space Structure Invariant Conditional Probability Distribution Chapter Versus Space Group Symmetry
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