Crystal parameters, data collection and structure refinement.

aThe values in parentheses refer to statistics in the highest bin. bRmerge = ∑hkl∑i|Ii(hkl)−|/∑hkl∑iIi(hkl), where Ii(hkl) is the intensity of an observation and is the mean value for its unique reflection; Summations are over all reflections. cR-factor = ∑h||Fo(h)|−|Fc(h)||/∑h|Fo(h)|, where |Fo| and |Fc| are the observed and calculated structure-factor amplitudes, respectively. dR-free was calculated with 5% of the data excluded from the refinement. eRoot-mean square-deviation from ideal values. fCategories were defined by Molprobity. Crystal parameters, data collection and structure refinement.