Patterson-oriented automatic structure determination. Deconvolution techniques in space groupP1

Several methods for the automatic determination of heavy-atom structures have been developed and extensively tested. The methods are based on a combination of vector superposition in space group P1 with a symmetry minimum function. The peaks of the symmetry minimum function are used as trial origin shifts in the translational search for the cell origin. Three or two Patterson shift vectors, all belonging to a single image, can be obtained for vector superposition by a procedure called cross-vector superposition. The superposition map may be refined by an automatic Fourier recycling in space group P1 before the translational search is started.