Hate to resurrect this, but I don’t think that the fchk utility is printing out the correct CC density after all.
This is a little bit of an odd test, but I am using the density matrix to calculate Hellmann-Feynman forces. When I use the CC density matrix, I get forces that are identical to those I get from using the SCF density matrix. Is there any way we can take a look at the fchk utility to make sure it is printing the right thing when called? I would be happy to help if pointed in the right place.
I have also tried adding:
to no avail.
(@andysim, I have a feeling you might also be able to help show me where to look for this)