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["Anglade Pierre-Matthieu" <anglade@gmail.com>]

You should ask Damien (caliste  at  pcpm/ucl/ac/be) on this matter.
The best I can say is that this implementation is totaly experimental.
For example two days before the release of 5.2 Damien has noticed that
everything in the new coultrtmt has been broken during the merge. If
you use this option you are doing experiments, not theoretical physics
:-).

On 7/27/06, dylu@ucdavis.edu <dylu@ucdavis.edu> wrote:
> Hello, dear abinit developers:
>        I have a few questions regarding the wavelets implementation in Abinit5.2 through 
> "icoultrtmt" and "nscforder". After reading the release notes and the BigDFT 
> webpage, though not much information available, I figured that it might be good for calculations 
> of non-periodic systems, since the Hartree and PSP local terms  are evalulated through Poisson 
> solver using open boundary conditions.
>
> 1. As for the example, v5_t07, why the K-point is shifted to 0.5 0.5 0.5 but 
> not on the Gama point, which seems to me a natural choice for cluster 
> calculations?
>
> 2. I expect the new method has a much better convergence regarding Etotal and 
> EHartree, if I understand it correct, since there is no image Coulomb 
> interaction. I modified the super cell size as the following in t07.in:
>
> ndtset 5
> acell: 3*5
> acell+ 3*2.5
>
> After a standard plane wave calculation using Abinit5.1.2, I got reasonable 
> numbers:
> [deyulu@zinfandel test512]$ grep Etotal *out
>     >>>>>>>>> Etotal= -3.24266940241069E-01
>     >>>>>>>>> Etotal= -4.26599328552894E-01
>     >>>>>>>>> Etotal= -4.42120273713403E-01
>     >>>>>>>>> Etotal= -4.44678592202608E-01
>     >>>>>>>>> Etotal= -4.45102876652833E-01
> [deyulu@zinfandel test512]$ grep "Hartree energy " *out
>     Hartree energy  =  1.32705836887717E-01
>     Hartree energy  =  1.38492352304226E-01
>     Hartree energy  =  1.56214176716576E-01
>     Hartree energy  =  1.74895165654710E-01
>     Hartree energy  =  1.90593035878911E-01
>
> Playing with the wavelets, the results seem to be very unstable.
> Can someone provide more information about this implementation and
> tell me what is going wrong?
>
> nscforder  8     # Order of scaling used by kernel
> !nscforder2 14
> !nscforder3 16
> !nscforder4 20
> !nscforder5 24
>
> [deyulu@zinfandel tmp]$ grep Etotal *out
>     >>>>>>>>> Etotal= -3.24272603801180E-01
>     >>>>>>>>> Etotal= -1.00569442580796E+00
>     >>>>>>>>> Etotal= -1.69531799128392E+00
>     >>>>>>>>> Etotal= -2.37427341162027E+00
>     >>>>>>>>> Etotal= -2.97559451789859E+00
>
>
> [deyulu@zinfandel tmp]$ grep "Hartree energy " *out
>     Hartree energy  =  3.89261939710595E-01
>     Hartree energy  =  4.31111370942495E-01
>     Hartree energy  =  5.26095331415071E-01
>     Hartree energy  =  5.72879491830780E-01
>     Hartree energy  =  5.85224698919510E-01
>
> Thanks
> Deyu Lu


--
Pierre-Matthieu Anglade