pikashu -create <a0> <structure> <spieces> <outputfile> [<formats>]
or
pikashu [<formats>] <outputfile> -create <a0> <structure> <spieces>
This mode allows to create a structure from scratch. For now, only a small number of very basic cubic structures can be created (see table below). Also, the base vectors of the created system are X=[100], Y=[010] and Z=[001]; other orientations are not implemented yet.
The parameters associated with the create
mode are:
The table below shows the acceptable entries for structure, and the corresponding number of spieces that must be specified:
structure | Number of spieces | |
---|---|---|
Simple cubic | sc | 1 |
Body-centered cubic | bcc | 1 |
Face-centered cubic | fcc | 1 |
Diamond | diamond, dia | 1 |
Zincblende | zincblende, zc | 2 |
Perovskite | perovskite, per | 3 |
The name of the <outputfile> can be specified either before or after the mode.
pikashu -create 4.02 fcc Al al_system.cfg
This will create a unit cell of fcc aluminium (lattice parameter=4.02 Å), and write it in the file al_system.cfg
.
pikashu -create 3.567 diamond C diamond.cfg xsf
This will create a unit cell diamond, and write it in the files diamond.cfg
and diamond.xsf
.
pikashu -create 5.431 dia Si silicon.cfg
This will create a unit cell of bulk silicon (diamond structure), and write it in the file silicon.cfg
.
pikashu sto.gin -create 3.86 perovskite Sr Ti O
This will create a unit cell of cubic strontium titanate (lattice parameter=3.86 Å), and write it in the file sto.gin
.
pikashu sto.xsf -create 3.86 perovskite Sr Ti O -expand 30 20 1
This example uses the expand option. It will create a unit cell of cubic strontium titanate, then expand it to form a 30x20x1 supercell. The final result will be output in the file sto.xsf
.