Methods for the separation of fast and slow atomic motions as a basis for analysis of nanoparticle dynamic structure

Numerical experiments with magic silver clusters (147, 309, and 561 atoms; molecular dynamics; and the Embedded Atom Model) have revealed the regular character of alteration in the function of the mean square displacement, which points to the high correlation of atomic motions in clusters. A detailed analysis of the mean square displacement functions of each atom has been performed using the example of a 147-atom cluster. A method for separating fast and slow motions has been employed which makes it possible to filter fast atomic motions. This method is based on the algorithms of trend elimination from the data and a determination of almost periods of oscillations. As a result of our analysis, the mean square displacement functions of the cluster atoms are classified by groups of similar plots with a high correlation.