[Pw_forum] How to decrease the forces on atoms for relaxation

[Elio Physics]

Hello  All,
I am trying to relax a system such that the force on each atom is less than 1 x10^(-4)  and P=0.0. I have succeeded in reducing P to zero by playing with the lattice parameter alat; however the force on few atoms is still large (10^(-2)).  I have 'vc-relaxed' the system but when I run the scf calculation the forces go back to the original unrelaxed structure... I have increased cutoff from 32 Ry to 40 Ry but this is not produce any significant changes. Is there any other parameter that can be changed to further reduce the forces on the atoms?
Thank you
Elio Nahdan

 		 	   		  
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