[Pw_forum] Convergence Problem

[Lorenzo Paulatto]

On Thu, 16 Apr 2009 03:43:33 +0200, å™é˜³ <sunyang198498 at gmail.com> wrote:
>     edir = 3
>     emaxpos=0.72
>     eopreg=0.28
Dear 孙阳,
This three lines mean that the field is inverted between 72% and 100% of the third basis vector, in your case along the z direction. In other words, the upper 28% percent of your cell is occupied the inverted field. The intensity of the inverted field is approximately 3 times larger than the direct field.

> ATOMIC_POSITIONS
> Pd       0.500000000   0.000000000  -1.496126804
> Pd       0.000000000   0.500000000  -1.496126804
> Pd       0.000000000   0.000000000  -1.002542052
> Pd       0.500000000   0.500000000  -1.002542051
> Pd       0.500000000   0.000000000  -0.501470158
> Pd       0.000000000   0.500000000  -0.501470158

All these atoms are in the inverted field region, maybe you have not understood correctly emaxpos and eopreg work. Please check you input to be sure you are actually doing what you want to do!

You can also increase the number of bands, reduce the beta mixing parameter and increasing the mixing_ndim parameter, but they cannot help if the input file has some error.

cheers

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Lorenzo Paulatto
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