Developments in the MITHRIL direct methods program

A major upgrade to the MITHRIL direct-methods computer program is described. This includes a symbolic addition module for centrosymmetric structures, an E magnitude filtering method, the generation of missing weak intensity data, the computation of standard deviations for E magnitudes and a review system for exploring structures where the figures of merit are contradictory. The program has also been re-dimensioned to allow larger structures to be attempted, and easy provision has been made for both the UNIX and VMS operating systems.