Author Topic: Triplet scf converges to singlet  (Read 34 times)

akn123

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Triplet scf converges to singlet
« on: March 26, 2020, 08:10:07 am »
Hello all,

I am new to Turbomole and was trying to do a single point energy calculation for a metal complex with triplet multiplicity just to check the occupancy of the generated mos. I started with eht generated orbitals with triplet occupation but when I run scf it converges to singlet. I have tried orbitalshift closedshell=1.0 and fermi annealing as well but it still gives me a singlet electronic configuration at the end. Is there a way to get a triplet wavefunction?

Thank you

antti_karttunen

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Re: Triplet scf converges to singlet
« Reply #1 on: March 26, 2020, 08:28:19 am »
Hi,

You could try using the "nue" option of the $fermi keyword:
Code: [Select]
$fermi tmstrt=300 tmend=20 tmfac=0.95 hlcrt=1.0E-01 stop=1.0E-03 nue=2
Here is the section from the manual:
The optional nue value (number of unpaired electrons) can be used to force a certain multiplicity in case of an unrestricted calculation. nue=0 is for singlet, nue=1 for dublet, etc.

I think you can avoid using closedshell shift and stick with the automatic shift.

Best,
Antti