[QE-users] cell_dofree with BFGS relaxation

[Lorenzo Paulatto]

> 1) Is this still the case? When I enable this setting in my own 
> calculations (QE v6.3) I see the cell does indeed allow only 
> z-relaxation in the cell, but it does so for all the lattice directions 
> rather than just the a_3 lattice direction.

In general cell_dofree works with BFGS, but it is true that some times 
damped dynamics is more reliable.

I.e. I recently did some relaxations with cell_dofree="shape", as BFGS 
was not findign the minimum for some volumes, I just put
   cell_dynamics="damp-pr"
   ion_dynamics = 'damp'
with everything default.

cheers

-- 
Lorenzo Paulatto - Paris