Firefly and PC GAMESS-related discussion club


 
Learn how to ask questions correctly  
 
 
We are NATO-free zone
 



Re: How to calculate Gibbs-free energy, enthalpy and entropy change in firefly?

sanya
sanya@photonics.ru


On Mon Feb 13 '12 8:21am, gensz wrote
-------------------------------------
>Hello there, I am confused on how to interpret the output file in firefly, I just want to know that, is the TOTAL ENeRGY in :ENERGY COMPONENTS: for the output file is equal to the Enthalpy?...

>since I worked on radicals I can't use runtyp=optimize for mp2, therefore i'll only use energy and it does not give me any information on Gibss-energy, Enthalpy and Entropy...
>
>
>Does the information in the HF calculations giving those reaction energies Gibbs,enthalpy and entropy is used for calculating the change in Gibbs-energy, change in Enthalpy and change in entropy?

>Pls help..I'm really confused.

For thermodynamic functions, you have to calculate hessian (RUNTYP=HESSIAN) for the optimized geometry of your molecule (RUNTYP=OPTIMIZE).

From your attached input files I do not see any radicals: ICHARG=0 MULT=1 and no ROHF is necessary.


[ Previous ] [ Next ] [ Index ]           Tue Feb 14 '12 1:11am
[ Reply ] [ Edit ] [ Delete ]           This message read 1432 times