[Pw_forum] time of scf and nscf computations

[Lorenzo Paulatto]

On 09/28/2013 02:44 PM, Paolo Giannozzi wrote:
> in principle, non-scf is faster. In practice, there isn't a
> large difference. It seems to me very strange that a non-scf
> calculation performed under exactly the same conditions is
> much slower than the scf one

I had the impression that SCF would diagonalize the empty bands with
reduced accuracy, while NSCF would diagonalize all the bands with full
accuracy. However, quickly checking the source code I found no trace of
my memory; possibly I did not recall correctly.

best regards

-- 
Dr. Lorenzo Paulatto
IdR @ IMPMC -- CNRS & Université Paris 6
phone:+33 (0)1 44275 084 / skype: paulatz
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