# ISMEAR and SIGMA

I'm calculating the total energy at the ACFDT-RPA level using VASP in terms of this tutorial. For the first three steps it uses:

ISMEAR = 0 ; SIGMA = 0.05


but for the final step does not use these parameters. I think there it takes default parameters. Does it make difference?

• The default value of ISMEAR is 1: vasp.at/wiki/wiki/index.php/ISMEAR
– Jack
Dec 23 '20 at 8:26
• Hi Savir, I suggest you edit the question title to add a little more info about what you intend to ask. "ISMEAR and SIGMA" makes it sound too general. Dec 23 '20 at 22:29

The defaults are ISMEAR=1 and SIGMA=0.2, which is quite different. If the energy is at all sensitive to SIGMA, then you may notice a slight difference in energies depending on which flags are used.