[CP2K:57] Re: New OT Algorithms

[Nichols A. Romero]

Valery,

Thanks for your comments. The benefits are for large systems and MD.

Is the speed up for MD _only_ for large system though? I'm am doing
MD on system sizes as small as 500 atoms as well as some large ones
(e.g. 4000+ atoms).

Thanks in advance for clarifying.

On 5/8/07, vweber <valer... at hotmail.com> wrote:
>
>
> Hi Nichols
>
> The new OT is basically a mapping of the orthogonality constrained
> energy functional to an unconstrained one.
> The orthogonality is enforced via a refinement polynomial.
> The minimization gets faster and faster while the wavefunction
> converges.
> It is, in the best case (e.g. during MD), about 2.5 faster than the
> standard OT (for what it replaces!).
> It converges the SCF like the standard OT or slightly faster
> especially if you dont update the preconditionner.
> As said Juerg, you really see the difference for large systems. For
> example a box of 512 waters will run (total time per SCF) 20% faster
> and
> 35% for 4096 waters. The speedup is much higher if no preconditionner
> is used.
> I would appreciate any feedback.
>
> Valery
>
>
>
>
>
> On May 7, 11:19 pm, "Nichols A. Romero" <naro... at gmail.com> wrote:
> > Hi,
> >
> > It would be nice if someone could comment on the advantages of the new
> OT
> > algorithm.
> >
> > Thanks,
> >
> > --
> > Nichols A. Romero, Ph.D.
> > 1613 Denise Dr. Apt. D
> > Forest Hill, MD 21050
> > 443-567-8328 (C)
> > 410-306-0709 (O)
>
>
> >
>


-- 
Nichols A. Romero, Ph.D.
1613 Denise Dr. Apt. D
Forest Hill, MD 21050
443-567-8328 (C)
410-306-0709 (O)
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