[Pw_forum] relaxation of the 60 C atom supercell

[Elie Moujaes]

Dear all,
I am still "fighting" with the 60 carbon atom system that I am trying to relax. I did a relaxation using 4 k-points and I got the system relaxed then I did an scf calculation with 25 points (for phonon calculations) and the total force is 0.099839. Does this mean that using 4 points is not enough? how many points do I have to consider as 25 points would really take a lot of time? Shall I relax for 10 k-points, the same as I was doing for an scf calculation? Can anyone advise me on that?
Thanks again and sorry to disturb you with that many times. I am trying to avoid the negative frequencies that I obtained before totally relaxing the crystal.

Elie MUniversity of Nottng7 2rduk 		 	   		  
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