[Pw_forum] Vc-relax

[Lex Kemper]

Hello everyone,

I have a question (or two, rather) regarding the vc-relax methods in PWSCF.
First, is there a need for a high energy cutoff, or high number of kpoints?
Second, having tried using it previously, I've found that the lattice 
constants are updated by very very small increments. What sets the scale 
on the size changes?

Thanks,

A.F. Kemper
Department of Physics and QTP
University of Florda