sci-chemistry Clashlist is a simple UNIX script which uses the awk facility along with the programs Probe and Cluster to build lists of van der Waals clashes from an input PDB-format molecular data file (with H atoms). These lists are organized such that collections of interacting residues are grouped together, sorted by the worst clash. For the purposes of this analysis, a clash is defined as a van der Waals overlap >= 0.4 A.