Adsorption energy = E(Adsorpted surface) - E(clean surface ) - E(Adsroptor)

Do three calculations and get three "free energy tot" in three OUTCARs, then the above formula to get the adsorption energy.

Thank you Wang Jinkai.

The above answer correctly tells how to calculate an adsorption energy, but it is not a Gibbs free energy, and also does not have zero-point energy corrections. To get the Gibbs free energy of adsorption (which is a function of temperature), you need to add corrections. One way to do this is to perform vibrational calculations (from the relaxed geometry) and use ASE's thermochemistry functions: https://wiki.fysik.dtu.dk/ase/ase/thermochemistry/thermochemistry.html . I believe you can do something similar with VASPKit and PyMatGen.

Thank you Matthew M. Montemore Thats where the problem starts for me. are the ASE codes compatible with VASP? or should I just use the thermochemistry function on VASPKIT?

Greetings, dear viewers!

In this video, we'll explore How to do Gibbs Free Energy Calculation for Oxygen Reduction Reaction (ORR) using VASP code . If you discover this information to be beneficial, kindly express your support by giving it a thumbs up, leaving a comment, and sharing it with others. We appreciate your viewership.

File Link: https://drive.google.com/file/d/1hhcjfbVpP48yUNdKY6aEc9xZo8otra5k/view?usp=sharing

Videos Links to watch:

1) Setting up a VASP calculation - Beginners https://www.youtube.com/watch?v=lUn9qVSlz3c

2) How to find the vibrational frequency of gas phase molecule https://www.youtube.com/watch?v=NmK_XavYt5E

3) Way to Find Entropy of Gas Phase Small Molecules https://www.youtube.com/watch?v=CLwrcBHq7Zg

4) How to get experimental ZPE and entropy of the gas phase molecules https://www.youtube.com/watch?v=wvEBS0Eu2QI

5) How to perform geometry optimization in VASP https://www.youtube.com/watch?v=S5fARRzbsgs

6) How to Perform Vibrational Frequency Calculation in VASP https://www.youtube.com/watch?v=WG7wubNGX2E

7) How to get ZPE and Entropy of the Adsorbed systems in VASP https://www.youtube.com/watch?v=ZyNUmDZqDM4

Warm regards, SB

Thank you Dr. Sambath Baskaran. I saw those videos recently on YouTube. they were really amazing and insightful. the vast community will appreciate that. well done.