[Pw_forum] questions on vc-relax

[Guoying Gao]

Dear everyone,
      I am doing structure optimization and set
"calculation=vc-relax", I'm confused  that it doesn't converge no
matter what I do. The following is what I have done:
     nstep=100, I tried dt with the values of 30,50,75,90,100,150
     Also, I do the above things with different pseudopotentials, the
results are still the same.
     I also read the truobleshooting in version of 3.2 of  manual and
Pw_forum, but I didn't find the suitable answers to my questions. The
only prossible method is to increase variables "etot_conv_thr" and
"forc_conv_thr", however, I don't know whether this will affect the
accuracy of calculating the properties of the structure.
Does anyone know the reason for this or the method to solve it?
Thank you in advance!

                        gao