next up previous contents index
Next: Syntax Up: Crystallographic Refinement Previous: Example: Refinement of

Grouped B-Factor and Occupancy Refinement

    The xrefin optimize group statement optimizes grouped B-factors and occupancies, e.g., two for each residue. The procedure minimizes the function . The Powell conjugate gradient minimization method is used. B-factors and occupancies can be refined simultaneously by specifying both the B and the Q options.

Uniform shifts are applied to the B-factors and occupancies for each of the selected groups. The optimization is started using the current values of the B-factors and occupancies, regardless of whether these values are identical within a particular group.

Web Manager
Sat Mar 11 09:37:37 PST 1995