spin contamination in cosmo


Just Got Here
yahoo

i want to calculate the solvation free energy of some transition metal compound at b3lyp/6-31G*. The calculation gives a value that shows a spin contamination higher than 10%. Can somebody help me on how shall I deal with this condition? please...

Forum Vet
I would assume you find the same spin-contamination when you do not include solvation. Removing spin-contamination requires a ROHF calculation instead of a UHF. See http://nwchemgit.github.io/index.php/Release61:Density_Functional_Theory_for_Molecules#CGMIN... for details. This only works for NWChem 6.1 and beyond.
Effectively, you need to add

  cgmin
rodft

to the DFT input block.

Bert


  [QUOTE=Mddabbler Jul 18th 1:54 pm]

i want to calculate the solvation free energy of some transition metal compound at b3lyp/6-31G*. The calculation gives a value that shows a spin contamination higher than 10%. Can somebody help me on how shall I deal with this condition? please...

Just Got Here
During optimization at b3lyp/6-31G(d), the spin contamination is tolerable. It is below 10%. The spin contamination only became a problem when I introduced solvation using vdW radius scaled by 1.2. Thank you Bert.


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