grain_dir direction overlap
direction= 1 or 2 or 3
overlap= real number
grain_dir 1 0.1 grain_dir 2 0.2
This command sets the grain stack direction and the overlap between adjacent grains along that direction, as shown in the figure below:
direction can be 1, 2, or 3, corresponding to the x, y, or z directions, respectively.
overlap, in units of the component of the lattice periodicity length vector along the
direction, sets the overlap distance between adjacent grains along the
direction, as shown in the figure above. It is used to adjust the relative position along a certain direction between adjacent grains to find the energy minimized grain boundary structure. If
overlap is a large positive real number, some atoms from adjacent grains may be too close to each other. In this case, one may use the cutoff style in the modify command to delete some atoms that are within a certain distance from others.
Note that the
direction is also the subdomain stack direction if
subdomain_number > 1 even when there is only one grain, i.e.,
grain_number = 1. Since there is no overlap between adjacent subdomains within the same grain,
overlap becomes irrelevant when
grain_number = 1.
This command becomes irrelevant when
boolean_restart = t, in which case there is no need for the grain information.
grain_dir 3 0.