contribution of vibrational entropy in gibbs free energy
Posted: Sat Nov 19, 2022 8:03 am
Hello,
Does the entropy term mentioned in the free energy table indicate the sum of contributions of translational, Rotational, and Vibrational degrees of freedom?
I calculated the vibrational frequency with IBRION = 5 for NSW = 1. Then using the following eqn calculated the vibrational entropy of a harmonic oscillator which gives 0.0057 eV. Therefore I am confused if I am missing anything here.
Does the entropy term mentioned in the free energy table indicate the sum of contributions of translational, Rotational, and Vibrational degrees of freedom?
Code: Select all
Free energy of the ion-electron system (eV)
---------------------------------------------------
alpha Z PSCENC = 1.79219085
Ewald energy TEWEN = 446.99159274
-Hartree energ DENC = -949.08121877
-exchange EXHF = 0.00000000
-V(xc)+E(xc) XCENC = 39.37578861
PAW double counting = 1454.99506404 -1425.33624586
entropy T*S EENTRO = 0.00301559
eigenvalues EBANDS = -239.48516022
atomic energy EATOM = 607.22751992
Solvation Ediel_sol = 0.00000000
---------------------------------------------------
free energy TOTEN = -63.51745310 eV
energy without entropy = -63.52046869 energy(sigma->0) = -63.51845829
I calculated the vibrational frequency with IBRION = 5 for NSW = 1. Then using the following eqn calculated the vibrational entropy of a harmonic oscillator which gives 0.0057 eV. Therefore I am confused if I am missing anything here.