entropy of the transition state and reaction rate

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abmo
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entropy of the transition state and reaction rate

#1 Post by abmo » Mon May 13, 2013 6:55 pm

Hi,

I would like to estimate the reaction rate constant for water dissociation over nickel surface. I have found the TST and several soft modes after frequency calculations and I am afraid if harmonic oscillator approximation fails in this case. I was wondering if I can use k=(kbT/h)exp(-∆G#/RT) approximation.
If yes, how can I find the entropy of the transition state (one needs the equation: ∆G#=∆H#-T∆S# where ∆H#=Htst-Hreact etc.)? Is the entropy written in OUTCAR? I prefer not to use vibrational frequencies because of soft modes.
If not,does any body know what method I can use?
It would be appreciated if some one could help me.

Regards
Abas
<span class='smallblacktext'>[ Edited ]</span>
Last edited by abmo on Mon May 13, 2013 6:55 pm, edited 1 time in total.

support_vasp
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Re: entropy of the transition state and reaction rate

#2 Post by support_vasp » Wed Sep 04, 2024 12:43 pm

Hi,

We're sorry that we didn’t answer your question. This does not live up to the quality of support that we aim to provide. The team has since expanded. If we can still help with your problem, please ask again in a new post, linking to this one, and we will answer as quickly as possible.

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