Molcas Forum

andrewshyichuk

Member

Registered: 2020-02-13

Posts: 62

A RASSCF calculation converges but rc is _RC_NOT_CONVERGED_

Dear Community,

I've encountered a problem summed up in the title.

In the RASSCF convergence section, I get "Convergence after  6 iterations", the overall output of a convergent calculation, and then the  rc=_RC_NOT_CONVERGED_ and ".# Convergence problem #." tail.
To make it more interesting, the .status file in the workdir says "Happy landing", while the rc. files say "96" - all created at the same time, in the same calculation. I even tried clearing the rc. files beforehand.
I will try runnig seward again to see if that helps.

TBH, this is a "restart calculation": the original RASSCF calculation did not converge in 200 steps, I than used the RasOrb.1 orbitals as a start orbitals and ran it again, which improved convergence - repeat that a few times and it's done. Except, sometimes it's not done, with the described symptoms.
Any ideas? 

The cosherness of this RasOrb.1 approach can be questioned - however, my argument for it is the fact that at the end it converges in a few steps, meaning that the RasOrb.1 orbitals are very close to the optimized/converged "correct" RASSCF orbitals, for the given setup.