Reverse Monte Carlo
Reverse Monte Carlo (RMC) [1] is a variation of the standard Metropolis Monte Carlo (MMC) method. It is used to produce a 3 dimensional atomic model that fits a set of measurements (Neutron-, X-ray-diffraction, EXAFS etc.). In addition to measured data a number of constraints based on prior knowledge of the system (like chemocal bonds etc.) can be applied. Some examples are:
- Closest approach between atoms (hard sphere potential)
- Coordination numbers.
- Angels in triplets of atoms.
The algorithm for RMC can be written:
- Start with a configuration of atoms with periodic boundary conditions. This can be a random or a crystalline configuration from a different simulation or model.
- Calculate the partial radial distribution functions Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle g_{\alpha \beta} (r) } for this configuration.
- Transform to the total structure factor:
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References
- R.L.McGreevy and L. Pusztai, Mol. Simulation, 1 359-367 (1988)