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Re: Is TOTAL FREE ENERGY IN SOLVENT (in a PCM energy calculation run output) really total?

Alex Granovsky
gran@classic.chem.msu.su


Dear Tatiana,

On Thu Mar 13 '14 3:58pm, Tatiana Alieva wrote
----------------------------------------------
>Hallo to all once more,

>The question in the title was vague for me all the time. I've failed to find a clear answer in the firefly documentation.
>1) Does TOTAL FREE ENERGY IN SOLVENT include entropy contribution of a solute?

It does not.
By default, it also does not include dispersion-repulsion terms
and cavitation free energy. These terms can be computed using
irep, idisp and icav keywords of $pcm group.


>And
>2) Why in e.g. MP2 energy calculation  FREE ENERGY IN SOLVENT =  E(0), not =E(MP2) from RHF-MP2 ENERGY CALCULATION?

This is a bug in printout, thanks for reporting it.
It will be fixed in the next beta of Firefly v. 8.1.0

Note though that the line below:

 ELECTROSTATIC INTERACTION = 1/2(PB+PC) + 1/2PX + UNZ=...

contains correct numbers.


>Perhaps, It would be a good thing if the contributions to the TOTAL FREE ENERGY IN SOLVENT were explicitly documented in the Firefly manual... If this term really doesn't include the entropy contribution from the solute, then better write down this explicitly.

I agree.

Kind regards,
Alex Granovsky





>I will be grateful for your answer.
>Tatiana


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