If you use Gaussian to carry out the calculation, and the point group of the dimer has been identified by Gaussian, then Gaussian will print irreducible representation (IRREP) of electronic state wavefunction and that of orbital wavefunction, you can examine the symmetry according to IRREP in the character table of corresponding point group.

Tian

Sorry for the confusion. The dimer has a certain spatial symmetry and I would like to check whether the wavefunction is symmetric or anti-symmetric under this symmetry operation.

Hope this is better explained.
Many thanks for your speedy reply,
Ivan

I don't understand what is the "parity" in the present context, is it a geometry property or a wavefunction property?

Best,

Tian

I am new to multiwfn and would like to use it to check parity (of dimers). I saw translations and roations are implemented. Is there also a way to perform spatial inversion (the overlap is then clearly documented)?

If this is not possible are you aware of another program that can help?

Many thanks for the nice program and support.

Bests,
Ivan