I know how to calculate the polyhedral packing fraction of simple crystal structures, but in a lot cases, the structure is not cubic and the polyhedra are irregular, and it becomes very tedious to calculate the polyhedral packing fractions by hand. I am wondering if anyone knows of any software that can calculate the polyhedral packing fractions based on an input structure file(i.e., a .cif file)?
For example, for some common oxides: NiO consists of densely packed octahedra, while ZnO consists of tetrahedra connected only by point-sharing (not densely packed). The polyhedral packing fraction of the former is much higher than that of the latter:
ADDENDUM for non crystallographers: