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Updated: Aug 9, 2026

Structural Studies of Macromolecules in Solution using Small Angle X-Ray Scattering
Published on: November 5, 2018
Biaxial tensors for anomalous scattering of X-rays in selenolanthionine
1Department of Chemistry, University of California, Berkeley 94720.
Abstract:
X-ray pleochroism is observed near the Se K absorption edge in a monoclinic crystal of selenolanthionine monohydrate using linearly polarized synchrotron radiation and is explained by a simple molecular-orbital model. The complex anomalous-scattering tensor of selenium, measured by diffraction in a tetraronal crystal of the anhydrous compound, exhibits anisotropy nearly 6 for f' and 7 for f", the most yet found for a K edge. The crystal structure was determined for D-(-)-selenolanthionine, space group P4(3)2(1)2, a = 6.651 (2), c = 21.758 (5) A, Z = 4, R = 0.027 for 304 unique reflections.
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