return a good supercell matrix
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| type(lo_crystalstructure), | intent(in) | :: | p | unitcell |
||
| integer, | intent(in) | :: | na | desired number of atoms |
||
| integer, | intent(out), | dimension(3,3) | :: | supercellmatrix | fashionable supercell matrix |