COSMO + oc correction

Questions
#1

We recently were trying out COSMO solvation in Q-Chem, and this is what I see in the final energy printout:

before final oc correction, ETot: -754.6341753525
number of outlayer segments: 428
SCF energy after oc correction: -754.6490823283
SCF energy in the final basis set = -754.6490823283
Total energy in the final basis set = -754.6341753525

I believe oc stands for outlying charge and therefore I should use the energy value after oc correction? If so, is there a reason that the “Total energy in the final basis set” omits this correction?

Thanks!
Samer

#2

it’s definitely the outlying charge correction (looking at the Q-Chem /COSMO interface code). The way that language about ‘SCF energy in the final basis set’ has gone away in recent versions of Q-Chem (starting with 6.1, I believe). It should be printed for dual-basis jobs, which is a niche case where that language makes sense, but for most SCF calculations it just confuses users. That said, I will implement a 1-line fix that changes “oc” to “outlying charge”, for clarity.

1 Like
#3

This has been fixed for the 6.2 release. “Outlying charge correction” is now spelled out and added to the total SCF energy. The “final basis set” language disappeared in v.6.1 except for dual-basis jobs.

#4

Thank you John! I was using Q-Chem 6.0.2, so this was before the “SCF energy” line was removed.