[Pw_forum] Example07

[Paolo Giannozzi]

On Oct 17, 2011, at 20:48 , W2AGZ wrote:

> Paragraph 1) of the README file contains the rather cryptic comment  
> with respect to the use of a 16 x 16 x 16 MP grid in an scf  
> calculation preparatory to calculating subsequent el-phon  
> coefficients, “Note that the k-point grids used here are NOT dense  
> enough for a serious calculation!!!”
>
I don't see anything cryptic: an example is an example and nobody  
should expect
realistic results from an example.
> Has such a calculation of the Eliashberg parameters of aluminum  
> using QE been published
>
it has been done (by me: the problem was the behavior of Tc under  
pressure), but never
published, because the result looked quite dull and did not add  
anything to previous, less sophisticated calculation. It was almost  
10 years ago. I used something like a 24x24x24 MP
grid (not translated) for the double-delta integration of the  
electron-phonon coefficients,
maybe even 32x32x32. This is by far the most critical parameter.

P.
---
Paolo Giannozzi, Dept of Chemistry&Physics&Environment,
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222