Acta Crystallographica Section A

Foundations of Crystallography

Volume 58, Part 1 (January 2002)

research papers

Acta Cryst. (2002). A58, 42-46 [ doi:10.1107/S0108767301015537 ]

A guided simulated annealing method for crystallography

C. I. Chou and T. K. Lee

Abstract: A new optimization algorithm, the guided simulated annealing method, for use in X-ray crystallographic studies is presented. In the traditional simulated annealing method, the search for the global minimum of a cost function is only determined by the ratio of energy change to the temperature. This method designs a new quality function to guide the search for a minimum. Using a multiresolution process, the method is much more efficient in finding the global minimum than the traditional method. Results for two large molecules, isoleucinomycin (C₆₀H₁₀₂N₆O₁₈) and an alkyl calix (C₇₂H₁₁₂O₈ · 4C₂H₆O), with different space groups are reported.

Keywords: simulated annealing.