Determination of Absolute Configuration by Laue Photographs

Abstract

WHEN a non-centrosymmetric crystal is studied by using X-rays of the wave-length λ a little shorter than the K- or L-absorption edge of some atom Z in the crystal, the hkl and h̄k̄l̄ reflexions should, in general, have different intensities. This effect was first observed by Coster, Knol and Prins^1,2, using zinc sulphide and gold Lα₂ radiation. The same method was used by Peerdeman, van Bommel and Bijvoet³, for sodium–rubidium tartrate and zirconium Kα radiation, in their beautiful confirmation of the correctness of the Fischer convention for optically active molecules. Bijvoet has also pointed out possible applications of the method, for example, in phase determination for non-centrosymmetric compounds⁴. The practicability of such applications is limited, however, by the difficulties of the technique.