Open AccessProtein Crystallography in the Soft X‐ray Region: Crystal Lifetime and Diffraction Efficiency
Author(s) -
Polikarpov I.
Publication year - 1997
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049596012009
Subject(s) - diffraction , x ray crystallography , absorption (acoustics) , crystallography , crystal (programming language) , crystal structure , materials science , chemistry , optics , physics , computer science , composite material , programming language
Multiwavelength anomalous diffraction on the sulfur (5.01 Å) and phosphorus (5.77 Å) absorption K ‐edges seems to offer a solution to one of the most appealing problems of protein crystallography – the determination of the phases of structure amplitudes. However, a strong increase in absorption of X‐rays in this region may impede the development of this method of structure solution. Analytical expressions for diffraction efficiency and normalized diffraction efficiency have been derived in the present paper. It is shown that the crystal lifetime in the soft X‐ray region will be significantly shorter than the lifetime of a macromolecular crystal exposed to 1–1.5 Å X‐rays during diffraction data collection. An optimum crystal size has been estimated.