[QE-users] What's representation 0 in ph.x?

[Lorenzo Paulatto]

> 1. When I do phonon calculation of isolated CO molecule with q points 
> sampling automatically 2x2x2, I find large negative frequency emerges in 
> DOS.

Hello Yike,
if it is an isolated molecule, only the phonons at Gamma make sense : 
there is no point in doing a 2x2x2 grid. If the negative frequencies are 
not at Gamma, there is nothing to worry about.

cheers

-- 
Lorenzo Paulatto - Paris