Application of the reverse Monte Carlo method to crystalline materials

An implementation of the reverse Monte Carlo (RMC) method for the study of crystalline materials from polycrystalline neutron total scattering data is presented. The new feature is that explicit account is taken of the intensities of Bragg peaks, which are extracted from the data using the Pawley method. The use of Bragg peaks ensures that the RMC models reproduce both the long-range and the short-range order reflected in the experimental data. The relative effects of different contributions to the data sets in the RMC method are assessed and successful applications are illustrated using the quartz and cristobalite polymorphs of silica as examples.

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