A fast fourier transform algorithm for the radial distribution function

Abstract

A simple fast Fourier transformation (FFT) algorithm has been specifically adapted to calculate the experimental radial distribution function. The number of equi-spaced data points must be a power of two [N = 2ⁿ for integer n] and must be greater than the Nyquist frequency [N = 2(^rmax) (^smax)/2π]. When properly defined, the data set is expanded as an odd function. The greatest advantage of the FFT algorithm is its internal consistency—the ability to exactly transform back to the original domain.