[Pw_forum] error on phonon calculation (root not converged)

[Paolo Giannozzi]

On Monday 10 April 2006 19:31, Liping YU wrote:

> 1x1x1 cell
> Total energy: -275.21362101 ( *4= -1100.85448404 )

> k = 0.0000 0.0000 0.0000 ( 1045 PWs) bands (ev):

> -45.3707 [...]

> 2x2x1 super cell
> Total energy: -1100.81820918

> k = 0.0000 0.0000 0.0000 ( 4189 PWs) bands (ev):

> -45.2796 -45.2775 -45.2775 -45.2757 [...]

total energies per cell are not the same. Also eigenvalues are clearly 
not the same. Your 2x2x1 supercell is not 4 times a 1x1x1 cell.

P.
-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
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