[Pw_forum] vc-relax

[Paolo Giannozzi]

On Wed, 2012-03-21 at 10:23 +0800, Cao TF wrote:

> I want to do the 'vc-relax' calculation of bilayer structure of graphene and BN. And only the lattice constant a, b are allowed to change in the relaxation. So I set cell_dofree = 'xy' , but when the calculation finished, the distance of of the vacuum between different by layers also changed. 

I am not sure that the constraints are implemented for all minimization
algorithms. Could you please provide an input and the corresponding 
output?

P.

-- 
Paolo Giannozzi, IOM-Democritos and University of Udine, Italy