Using X-ray absorption spectra to monitor specific radiation damage to anomalously scattering atoms in macromolecular crystallography

It is shown that two major causes of `white-line' variation at the bromine K-absorption edge are, first, the dose-dependent cleavage of C-Br bonds and, second, the crystal orientation versus the beam polarization. The former effect allows monitoring the cleavage of anomalously scattering atoms during data collection, which is important for the RIP method.