6
$\begingroup$

enter image description here

Which is my ecutwfc converged value in this calculation result.

How to choose ecutrho in quantum espresso calculation.

$\endgroup$
6
$\begingroup$

Convergence is always defined in term of tolerance what user choose and based on your data, I will take ecutwfc as 70 Ryd. You should also report run time along with these data. For considering ecutrho I will suggest you to stick with default value, if you are dealing with metallic system.

Kinetic energy cutoff (Ry) for charge density and potential: For norm-conserving pseudopotential you should stick to the default value, you can reduce it by a little but it will introduce noise especially on forces and stress. If there are ultrasoft PP, a larger value than the default is often desirable (ecutrho = 8 to 12 times ecutwfc, typically). PAW datasets can often be used at 4*ecutwfc, but it depends on the shape of augmentation charge: testing is mandatory. The use of gradient-corrected functional, especially in cells with vacuum, or for pseudopotential without non-linear core correction, usually requires an higher values of ecutrho to be accurately converged.

References:

https://www.quantum-espresso.org/Doc/INPUT_PW.html#idm274

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.