Molecular dynamics simulations of the nanometer-scale mechanical properties of compressed Buckminsterfullerene

Molecular dynamics simulation techniques and an analytic many-body potential function have been used to study a spherical C,,, cluster (“Buckminsterfullerene”) compressed between graphite planes. We find that the cluster can reversibly deform under anisotropic compression to a radius (in the direction of compression) that is l/3 that of the uncompressed cluster. On compression the restoring pressure first rises and then exhibits a distinct drop beginning at a pressure of about 3 GPa. This drop in pressure is a result of a reversible change which occurs when the cluster transforms to a disc-like structure. Further compression results in a rise in pressure with a slope direrent from the initial compression.