MCGRtof: Monte Carlo G(r) with resolution corrections for time-of-flight neutron diffractometers

A new implementation of the program MCGR [Pusztai & McGreevy (1997). Physica B, 234-236, 357-358] for the calculation of pair distribution functions from neutron total scattering data using an inverse Monte Carlo algorithm is presented. The new implementation, called MCGRtof, incorporates the resolution functions for time-of-flight neutron diffractometers, and is suitable for analysis of data from instruments such as GEM at the ISIS spallation neutron source. The effect of including resolution correctly is to increase the magnitude of the pair distribution function at larger distances. The working program is illustrated with total scattering measurements from crystalline AlPO₄.