QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: hsuya on February 26, 2020, 07:27

Title: Performing physisorption
Post by: hsuya on February 26, 2020, 07:27

Is there a way to differently perform or distinguish whether a particular adsorption is physisorption or chemisorption?

Title: Re: Performing physisorption
Post by: Nordland on February 27, 2020, 15:07

From an ab-initio simulation point of view, it would be the same calculation.

Hand-waving we would call reaction with a low energy gain for physisorption and those with a high energy gain for chemisorption.

Another way to quantify it would be to look at the molecular levels of the molecule alone versus the molecule on the surface.
According to Wikipedia:
Physisorption, also called physical adsorption, is a process in which the electronic structure of the atom or molecule is barely perturbed upon adsorption.

Therefore if you compare the molecular spectrum of both cases, and they are similar, you could classify it as physisorption. If they are significantly changed,  then you could classify it as chemisorption

Title: Re: Performing physisorption
Post by: hsuya on March 3, 2020, 06:40

Thanks a lot for the detailed explanation  :D