Procedural difficulties, encountered during an X ray crystal structure determination of a heavy atom derivative, with space group C2 and Z = 4, are reported and discussed. The scarcity of similar experiences in the crystallographic literature has suggested a review of the possible procedures for non-centrosymmetric space groups. A sort of «trial and error» method, to prevent occurrence of false peaks and related excessively high expenses in computer time, is described.
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Con il contributo del Ministero per i Beni e le Attività Culturali