Tables for
Volume B
Reciprocal space
Edited by U. Shmueli

International Tables for Crystallography (2006). Vol. B. ch. 2.3, p. 242   | 1 | 2 |


M. G. Rossmanna* and E. Arnoldb

aDepartment of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, USA, and  bCABM & Rutgers University, 679 Hoes Lane, Piscataway, New Jersey 08854-5638, USA
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Three different cases which can occur in the relation of the native, [{\bf F}_{N}], and heavy-atom derivative, [{\bf F}_{NH}], structure factors for centrosymmetric reflections. [{\bf F}_{N}] is assumed to have a phase of 0, although analogous diagrams could be drawn when [{\bf F}_{N}] has a phase of π. The crossover situation in (c) is clearly rare if the heavy-atom substitution is small compared to the native molecule, and can in general be neglected.