Tables for
Volume F
Crystallography of biological macromolecules
Edited by E. Arnold, D. M. Himmel and M. G. Rossmann

International Tables for Crystallography (2012). Vol. F, ch. 16.1, p. 424   | 1 | 2 |


G. M. Sheldrick,a C. J. Gilmore,b H. A. Hauptman,c C. M. Weeks,c* R. Millerc and I. Usónd

aLehrstuhl für Strukturchemie, Georg-August-Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany,bDepartment of Chemistry, University of Glasgow, Glasgow G12 8QQ, UK,cHauptman–Woodward Medical Research Institute, Inc., 700 Ellicott Street, Buffalo, NY 14203–1102, USA, and dInstitució Catalana de Recerca i Estudis Avançats at IBMB-CSIC, Barcelona Science Park. Baldiri Reixach 15, 08028 Barcelona, Spain
Correspondence e-mail:


(a) Success rates and (b) cost effectiveness for several dual-space strategies as applied to a 148-atom P1 structure. The phase-refinement strategies are: (PS) parameter-shift reduction of the minimal-function value, (TE) Karle-type tangent expansion (holding the top 40% highest [E_{c}] fixed) and (NR) no phase refinement but Sim (1959)[link] weights applied in the E map (these depend on [E_{c}] and so cannot be employed after phase refinement). The real-space strategies are: (PP) simple peak picking using [0.8 N_{u}] peaks, (PO) peaklist optimization (reducing [N_{u}] peaks to [2 N_{u}/3]), and (RO) random omit maps (also reducing [N_{u}] peaks to [2N_{u}/3]). A total of about 10 000 trials of 400 internal loop cycles each were used to construct this diagram.