Firefly and PC GAMESS-related discussion club

 
Learn how to ask questions correctly  
 
 

 

Alex Granovsky
gran@classic.chem.msu.su

sorry for overlooking that.

Actually my question was on the origin of -18.394 KJ/MOL correction.
I see it is taken from the vibration analysis, is it?.

I think PCM energies you have computed do not include these types
of contributions. It would be more correct to compare -100.426656 H directly with -100.433893 H and -100.430009 H.

All the best,
Alex


On Thu Feb 20 '14 2:51am, David G. wrote
----------------------------------------
>>Dear Alex

>Yes it is. The HF.out in attached zip file shows the result.

>Sincerely, D.
>
>
>
>On Thu Feb 20 '14 2:40am, Alex Granovsky wrote
>----------------------------------------------
>>Dear David,

>>> -100.426656 : FINAL ENERGY (Hartree)

>>is this energy computed for the gas phase i.e. with no PCM at all?

>>All the best,
>>Alex
>>
>>
>>On Thu Feb 20 '14 2:26am, David G. wrote
>>----------------------------------------
>>>>Dear Alex

>>>in the following you can find the values and their description. The total G as reported by FF does't include electronic part so I have added final energy to make the free energy that could be compared with the free energy reported by FF in PCM calculations.
>>>
>>>
>>>
>>>-100.426656 : FINAL ENERGY (Hartree)

>>>-18.394: TOTAL G (KJ/MOL)

>>>2625.5: converts KJ/MOL to Hartree

>>>-100.433662: free energy (Hartree)
>>>
>>>
>>>Sincerely Yours
>>>David
>>>
>>>
>>>
>>>
>>>On Thu Feb 20 '14 0:19am, Alex Granovsky wrote
>>>----------------------------------------------
>>>>Hi,

>>>>Dear David,

>>>>how exactly were the numbers below obtained?

>>>>>free energy of HF (gaseous) : -100.426656 - 18.394/2625.5 = -100.433662 H

>>>>Could you comment on the -100.426656 - 18.394/2625.5  math?

>>>>Kind regards,
>>>>Alex Granovsky.
>>>>
>>>>
>>>>
>>>>On Thu Feb 13 '14 6:33am, David G. wrote
>>>>----------------------------------------
>>>>>Hi

>>>>>As a test to understand how Firefly does compute and consider solvent effects the free energy of HF diatomic molecule has been calculated in gaseous state, water, and benzene to compare the results.

>>>>>free energy of HF (gaseous) : -100.426656 - 18.394/2625.5 = -100.433662 H
>>>>>free energy of HF (water): -100.433893 H
>>>>>free energy of HF (benzene): -100.430009 H

>>>>>we expected a larger difference between the values in water and benzene since HF is a highly polar molecule. I have attached the input/output files and I appreciate any comment to help us how to improve the results if it looks unwise in this state. Many Thanks
>>>>>
>>>>>
>>>>>Sincerely, David
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>