Author Topic: Total free energy  (Read 2549 times)

0 Members and 1 Guest are viewing this topic.

Offline Dipankar Saha

  • Supreme QuantumATK Wizard
  • *****
  • Posts: 516
  • Country: in
  • Reputation: 5
    • View Profile
Total free energy
« on: October 27, 2018, 14:18 »
Hi,

How the 'Total free energy' is different from the 'Total energy (broadening->0)' ?

Thanks and Regards_
Dipankar

Offline Petr Khomyakov

  • QuantumATK Staff
  • Supreme QuantumATK Wizard
  • *****
  • Posts: 1290
  • Country: dk
  • Reputation: 25
    • View Profile
Re: Total free energy
« Reply #1 on: October 29, 2018, 10:24 »
The total energy is computed for a given broadening quantified with some artificial temperature when setting the calculator. Even so this is an artificial temperature introduced to speed up convergence of SCF, there is an entropy term -T*S in the corresponding free energy expression ('Total free energy' at T<> 0 K). The true ground state energy (i.e., at T=0 K) is given by  'Total energy (broadening->0)' .

Offline Dipankar Saha

  • Supreme QuantumATK Wizard
  • *****
  • Posts: 516
  • Country: in
  • Reputation: 5
    • View Profile
Re: Total free energy
« Reply #2 on: October 29, 2018, 10:56 »
Okay... I understand. Thank you!