I have encountered a problem when I'm using the current version of GoodVibes to deal with a Gaussian ONIOM (B3LYP:Amber) log file. I set the frequency scaling factor of both QM and MM regions to 1 by setting -v 1.0 --vmm 1.0, and I used the output T.S and G(T) data w/o entropic quasi-harmonic treatment, so the GoodVibes-calculated thermodynamics data should be absolutely identical to the data in the Gaussian log file. Despite the minor difference (-0.000001 Hartree) in the E, ZPE, and H values, I found that the calculated G(T) term has a major difference (-0.028425 Hartree) from the Gaussian log file Gibbs free energy value (denoted by "Sum of electronic and thermal Free Energies"). The reason is that the GoodVibes-calculated T.S (1.339317 Hartree) is different from the Gaussian output value (1.367742 Hartree = "Sum of electronic and thermal Enthalpies" minus "Sum of electronic and thermal Free Energies") although I have set both QM and MM scaling factors to 1.0 and didn't use the T.qh-S and qh-G(T) values. This discrepancy between Gaussian log file data and GoodVibes-recalculated values does not happen in pure QM calculations. Can you suggest if there is anything going wrong with the calculation? Thank you!
Dear GoodVibes developers,
I have encountered a problem when I'm using the current version of GoodVibes to deal with a Gaussian ONIOM (B3LYP:Amber) log file. I set the frequency scaling factor of both QM and MM regions to 1 by setting -v 1.0 --vmm 1.0, and I used the output T.S and G(T) data w/o entropic quasi-harmonic treatment, so the GoodVibes-calculated thermodynamics data should be absolutely identical to the data in the Gaussian log file. Despite the minor difference (-0.000001 Hartree) in the E, ZPE, and H values, I found that the calculated G(T) term has a major difference (-0.028425 Hartree) from the Gaussian log file Gibbs free energy value (denoted by "Sum of electronic and thermal Free Energies"). The reason is that the GoodVibes-calculated T.S (1.339317 Hartree) is different from the Gaussian output value (1.367742 Hartree = "Sum of electronic and thermal Enthalpies" minus "Sum of electronic and thermal Free Energies") although I have set both QM and MM scaling factors to 1.0 and didn't use the T.qh-S and qh-G(T) values. This discrepancy between Gaussian log file data and GoodVibes-recalculated values does not happen in pure QM calculations. Can you suggest if there is anything going wrong with the calculation? Thank you!