[Pw_forum] K_POINTS and Monkhorst-pack grids (nq1,nq2,nq3)

[Ker Park]

Hi all,
I have a question regarding phonon dispersion calculation.Shouldn't Monkhorst-pack grids (nq1, nq2, nq3) in 'ph.in' input file be the same as K_POINTS in SCF calculation ?I have the scf calculation results with  the K_POINTS set as 9 9 3 0 0 0 and tried to run pw.x calculation with nq1 = 9 , nq2 = 9, nq3 = 3,but the program complained with 'q-mesh breaks symmetry'Could the monkhorst-pack grids be something else such as nq1=4, nq2=4, nq3=4?Thank you.
Ker 		 	   		  
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