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Calculating entropy and ZPE before and after adsorption

Posted: Mon Jul 24, 2017 6:14 am
by lexa
Hi,

I want to calculate the Gibbs free energy of a reaction where a molecule adsorbs to the surface.

I am wondering whether your scripts allows the calculation of the entropy and zero point energies of the adrobate before and after adsorption?

Thanks,
Alexandra

Re: Calculating entropy and ZPE before and after adsorption

Posted: Mon Jul 24, 2017 2:19 pm
by graeme
The scripts can be used to calculate the vibrational modes, zero point energies, and vibrational entropies. For the gas phase species, however, you will need to include the translational entropy, based upon the temperature and pressure, yourself.

Re: Calculating entropy and ZPE before and after adsorption

Posted: Tue Jul 25, 2017 1:04 am
by lexa
Can you please tell me which script is used to obtain the vibrational entropy term? have used dymzpbar.pl to obtain the ZPE and that works.

Thanks

Re: Calculating entropy and ZPE before and after adsorption

Posted: Tue Jul 25, 2017 1:22 am
by graeme
Ah, I think we just calculate the ratio of vibrational partition functions. For the entropy, you can take the set of vibrational frequencies and calculate:
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Re: Calculating entropy and ZPE before and after adsorption

Posted: Sat Jun 04, 2022 1:58 pm
by zeesham_66
What is omega_v in this equation?

Thanks