Dear all,
I am using xds (with graphical interface xdsgui) to process several
diffraction data of a membrane protein that I have crystallized. At the
end, I run XDSSTAT in order to check the statistic parameters of the
process and my attention is captured by the R_d plot: R_d drops during
the firsts 10-15 frames and then reaches a maximum (20-30 frames). Then,
its value remains quite stable (I suppose due to the radiation damage
correction performed by xds). The trend seems the same that is shown in
ActaCryst. (2006). D62, 96–101 where "Some aspects of quantitative
analysis and correction of radiation damage"
Fig.1(a)(b)
where R_d (decay R-factor) was introduced.
The question is:
By considering that radiation damage increases during the data
collection due to the progressive dose of radiation to which the crystal
is subjected, why does the R_d drop during the first period of data
collection?
Thank you in advance for your answers.
Danilo
