There are two ways to specify this. Cartesian coordinates can be used
%BLOCK LATTICE_CART units
Where, for example, is the x-component of the second
lattice vector and is the z-component of the third
lattice vector and so on.
The supercell can also be defined in terms of the magnitudes of the lattice vectors
%BLOCK LATTICE_ABC units
, and are the magnitudes of , and and , and are the values of , and .
In both cases if [units] are not specified default units of Å are automatically used. However, angles must be specified in degrees.