Computing electronic free energy

[dEnvar]

Good afternoon,

I am working with a program which takes in an electronic density of states (DOS) file generated by VASP and then computes the electronic free energy F:
F=E-TS,
by using the DOS data. It does so by using integrals over the DOS with the Fermi-Dirac distribution, e.g. the internal mean energy in a heat bath at temperature T is:
<E> = int E*g(E)*f(E,T)*dE, where f(E,T) is the Fermi-Dirac distribution and g(E)*dE is the number of states per unit cell (as output from VASP).
The entropy is similarly computed using the DOS data.

My questions are:
1) The "total energy" as computed by VASP is that the total eletronic energy computed from the integral stated above?
In other words: If I have the output energy from VASP do I need to compute the electronic energy using the DOS or is that just redundant work?
2) Does VASP output electronic entropy?
If so, then I don't see why this program uses the DOS instead of the data given directly by VASP. Or am I missing something?

Thank you.

[support_vasp]

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.

Best wishes,

VASP