Symmetry-adapted pair distribution function analysis (SAPA): a novel approach to evaluating lattice dynamics and local distortions from total scattering data.

A novel symmetry-adapted pair distribution function analysis (SAPA) method for extracting information on local distortions from pair distribution function data is introduced. The implementation of SAPA is demonstrated in the software using the freely available online software , and scripts for converting the output from to a SAPA input file for are provided. Finally, two examples are provided to show how SAPA can evaluate the nature of both dynamic distortions in ScF and the distortions which act as an order parameter for the phase transitions in BaTiO.