[CPMD-list] Geometry optimization and misrepresentation of the x-ray data...

[Pedro Nuno Simões]

Dear Axel

Thanks a lot for your valuable assistance.

Best regards,
Pedro.


Axel Kohlmeyer escreveu:
> On Fri, 25 Apr 2008, Pedro Nuno Simões wrote:
>
> PNS> Dear Axel
>
> dear pedro,
>
> PNS> I accept your criticism. But as I firstly said, I am a beginner 
> PNS> both in CPMD code and CPMD mailing list, and I assume my lack of 
> PNS> experience in the field. Obviously, I had no intention to make 
>
> i understand that, but that is exactly why it needs to be said
> repeatedly and why the CPMD manual _does_ contain references 
> to web pages that _explain_ how to report problems. 
>
> PNS> things difficult. The complete
>
>
> PNS> input is attached.
>
> ok, so i just ran the minimal test:
>
> WAVEFUNCTION OPTIMIZATION, 
> MAXSTEP 1, CUTOFF 10
>
> added RHOOUT to the &CPMD section
> and cpmd2cubed the resulting DENSITY file
> to be viewed in VMD (including periodicity.
>
> => your system has "holes" so it looks like
> there is an additional symmetry (inversion?)
> in your CIF file that you have not replicated?
>
> also, it looks like you will have to think about
> how much your structure is determined by dispersion
> interactions, and how you are going to deal with
> it. as current GGA-DFT functionals tend to largely
> underrepresent those interactions.
>
> cheers,
>    axel.
>
>   


-- 
----------------------
Pedro Nuno N.L. Simões

Departamento de Engenharia Química
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