fix_modify AtC mesh create_nodeset <id> <xmin> <xmax> <ymin> <ymax> <zmin> <zmax>
fix_modify AtC mesh create_nodeset lbc -12.1 -11.9 -12 12 -12 12
Command to assign an id to a set of FE nodes to be used subsequently in defining boundary conditions.
Coordinates are assumed to be in lattice units.