How we can obtain the entropy (TS) and the potential value (U) to get Gibbs free energy
Posted: Sun Jun 04, 2023 4:22 am
Hello Colleagues,
I need to apply the Computational Hydrogen Electrode (CHE) model for the electroreductions. Therefore, I should calculate the Gibbs free energy by using this equation, G = E + ZPE - TS + U. E is DFT energy of the calculation, and we can get ZPE from the frequency calculations (sum of all the energy of all modes (minus 3 for translation)).
I have two questions regarding this:
The first one is that how we can calculate the entropy, TS, by using the frequency calculation output data, and can I apply this equation to compute the TS values, T*S = R * ∑[ν * ln(ν/T)], v- the vibrational frequency, R is the gas constant, and T is the temperature in Kelvin?
The other one is how we can get the value for the potential, U, to calculate the Gibbs energy.
I have attached a file of all vibrational frequency modes, and could you please explain for me to calculate the entropy and the potential with details by using this file.
Thank you.
I need to apply the Computational Hydrogen Electrode (CHE) model for the electroreductions. Therefore, I should calculate the Gibbs free energy by using this equation, G = E + ZPE - TS + U. E is DFT energy of the calculation, and we can get ZPE from the frequency calculations (sum of all the energy of all modes (minus 3 for translation)).
I have two questions regarding this:
The first one is that how we can calculate the entropy, TS, by using the frequency calculation output data, and can I apply this equation to compute the TS values, T*S = R * ∑[ν * ln(ν/T)], v- the vibrational frequency, R is the gas constant, and T is the temperature in Kelvin?
The other one is how we can get the value for the potential, U, to calculate the Gibbs energy.
I have attached a file of all vibrational frequency modes, and could you please explain for me to calculate the entropy and the potential with details by using this file.
Thank you.