####################################################################### # # # Example: Making a screw dislocation with the SCREW command # # # ####################################################################### # # # The SCREW command displaces the *selected* atoms to form a # # screw dislocation in a previously perfect lattice. # # # ####################################################################### # # # The format of the SCREW command is # # # # SCREW xburgers yburgers zburgers xorg yorg zorg [xref yref zref] # # # # where xburgers the components of the burgers vector # # yburgers # # zburgers # # xorg a point through which the screw axis passes # # yorg # # zorg # # xref optional, a vector non-parallel with the # # yref burgers vector. Those atoms which lie in # # zref plane containing this and the burgers vector # # will have a zero displacement. If this # # option is not specified, then the plane of # # zero displacement will be defined by an # # arbitrary vector # # # ####################################################################### # # # Create an FCC lattice with unit cell length of 1 angstrom # box 4 4 4 particle 4 1 0.25 0.25 0.25 1 0.25 0.75 0.75 1 0.75 0.25 0.75 1 0.75 0.75 0.25 dup 3 1 0 0 dup 3 0 1 0 dup 3 0 0 1 # # # Write coordinates # step 0 write cor screw.cor # # # Insert screw dislocation # screw 0 0 1 2.25 2.25 2.25 1 0 0 # # # Write coordinates step 1 write cor +screw.cor