Monday, June 05, 2006
No CIS(D) in solvent [Gaussian]
I tried to calculate excitation energy with CIS(D) method in solvent (PCM method). I found that the CIS resalts from CIS and CIS(D) outout are different. I checked and CIS with Direct and without this option gave another results. I wrote to Gaussian Help and got replay: Yes, there are differences and the CIS=Direct results are correct.The non-direct methods, both CIS and CIS(D) use MO integrals where the solvent effects are not present and thus neither of them will give the correct results. Starting with G03 Rev. D the program correctly forces the use of CIS=Direct when combined with solvation. There is no option for doing CIS(D) with solvent and I don't expect this to change. Sorry for any confusion.