Dear Jonas,
I tried using pymatgen to extract the point-symmetry information from your .xyz file (see the Python script below):
from pymatgen.core import Molecule
from pymatgen.symmetry import analyzer
bigstructure = Molecule.from_file("yourfile.xyz")
PGstructure = analyzer.PointGroupAnalyzer(bigstructure)
sym_mol = PGstructure.get_equivalent_atoms()
print(sym_mol["eq_sets"])
This returns a Python data structure containing the symmetry-irreducible sets of atoms (only 6 for this system, which is indeed of Ih point group!).
When preparing the CRYSTAL input, be careful with the orientation of your asymmetric unit. In my case, for example, I had to change the sign of the x and y coordinates to make the symmetry consistent with CRYSTAL’s conventions.
Icosahedral point groups are available in CRYSTAL (Ih is point group number 47 in CRYSTAL), so the input fort this molecular cage reads:
Symm. structure
MOLECULE
47
6
8 2.605032231 -11.914271806 11.762689798
6 4.344538598 15.664236912 4.366798884
6 3.427479683 14.428996321 8.326818862
6 -8.906580884 1.370529673 14.411150640
1 2.632960331 14.962480562 7.832453804
5 -8.776255231 -2.916256114 14.200279302
COORPRT
TESTGEOM
END
aerba Christmas is already in the air indeed!
