Molcas Forum

ethanthomas

Member

Registered: 2018-07-17

Posts: 4

molcas gv MOs symmetry

Hello,
I am trying to do calculations using symmetry. When I get the HF orbitals (for CASSCF/CASPT2 calculations), I select the ones that I want to include in the active space using molcas gv. However, if I do so, I notice that the MOs are not ordered by energy, but by symmetry. Is there any option in molcas gv that is able to order the MOs by energy?

Best,

ET

Ignacio

Administrator

From: Uppsala

Registered: 2015-11-03

Posts: 1,085

Re: molcas gv MOs symmetry

I don't think there is, at least not if you want to keep the symmetry information. You can probably use EXPBAS (DESYM keyword) to discard the symmetry and then the orbitals can be ordered by energy only. But, if your aim is selecting an active space for CASSCF, having the orbitals sorted by symmetry is the correct thing, since this is what the RASSCF program expects.

ethanthomas

Member

Registered: 2018-07-17

Posts: 4

Re: molcas gv MOs symmetry

Thanks!

valera

Administrator

Registered: 2015-11-03

Posts: 129

Re: molcas gv MOs symmetry

GV does not sort orbitals - it just visualize them. But grid_it, which generates grids can sort them by various ways (see docs).

ethanthomas

Member

Registered: 2018-07-17

Posts: 4

Re: molcas gv MOs symmetry

I just checked the docs and it is funny because there is an option for grid_it which is called "NoSort" which "Do not sort orbitals by occupation numbers and orbital energies". And that is the opposite what I want. 

Thanks!