Efficient analysis of molecular dynamics data

The problem of obtaining the space-time Fourier transform of the displacement-displacement correlation function from the results of a molecular dynamics calculation is considered. It is found that the correlation function is most efficiently constructed if one selects only one data point from each statistically independent space-time element and that noise is suppressed in the Fourier transform if one averages over frequency and wavevector, which is equivalent to introducing damping factors in integrals over the space and time variables. Results of numerical experiments which support these conclusions are given and a comment pertaining to the adequacy of a molecular dynamics algorithm is made. © 1976.