X-ray data collection and refinement statistics.

1Numbers in parentheses indicate values for the highest resolution bin.2Rsym = ∑[Ii−](100)/∑[] where i is ith measurement and is the weighted mean of I.3Rwork = ∑||Fobs|−|Fcalc||/∑|Fobs|.4Rfree is calculated using the same equation as for Rwork but using only the reflections randomly omitted from refinement reserved in the test set of the data.