[molpro-user] CCSD(T) RHF not converging

[Jörg Saßmannshausen]

Hi Kirk,

thanks for the reply.
I am currently trying it with the 
hf,maxit=300
lets see if that is working.
The MP2 calculation was performed with a different program and a different 
basis set. That seemed to have worked without much problems. 

I am not sure about the HF/6-31G* before I am doing the HF/cc-pVTZ 
calculation. I actually have tried that (with a different program) but I was 
unable to read the MO (which probably makes sense if one thinks about it).
So the input would be something like that:

basis=6-31G*
hf
basis=cc-pVTZ
hf
ccsd(t)

or?

Lets see if it is picking up the 300 iterations this time and if it is 
converging. 

All the best from Glasgow!

Jörg

On Tuesday 28 July 2009 17:22:50 Kirk Peterson wrote:
> Jörg,
>
> in terms of the maxit option try either
>
> hf,maxit=100
>
> or
>
> hf;maxit,100
>
> You mention the structure was optimized at the MP2 level.  Was this
> with Molpro and did you not see
> HF convergence problems there?  You could perhaps try put a HF/6-31G*
> calculation in front of  your
> cc-pVTZ one to see if that will generate better starting orbitals.
>
> regards,
>
> Kirk
>
> On Jul 28, 2009, at 3:16 AM, Jörg Saßmannshausen wrote:
> > Dear Sarandis,
> >
> > thanks for the swift reply.
> >
> > I am trying it now as a serial run, see if that makes a difference.
> >
> > What I cannot work out is, despite setting
> > maxit=300
> > or
> > gmaxit=300
> > I still get
> > MAX. NUMBER OF ITERATIONS:       60
> > in the
> > 1PROGRAM * RHF-SCF (CLOSED SHELL)
> > section of the output. Anybody an idea what I am doing wrong here?
> >
> > All the best
> >
> > Jörg
> >
> > On Tuesday 28 July 2009 10:15:23 you wrote:
> >> Dear  Jörg, hello
> >>
> >> I am having a similar problem with ccsd(t) calculations using
> >>
> >> 2006.1 molpro running in 8 parallel processors. In the past,
> >>
> >> the same input was ok for sequential run on a different computer.
> >>
> >> I was wondering whether you experience the same problem if
> >>
> >> you run it on a sequential mode? I think by the end of today,
> >>
> >> I will be able to see whether the problem with my input file appears
> >>
> >> only in the parallel version ...
> >>
> >> With best wishes,
> >> Sarandis
> >
> > --
> > *************************************************************
> > Jörg Saßmannshausen
> > Research Fellow
> > University of Strathclyde
> > Department of Pure and Applied Chemistry
> > 295 Cathedral St.
> > Glasgow
> > G1 1XL
> >
> > email: jorg.sassmannshausen at strath.ac.uk
> > web: http://sassy.formativ.net
> >
> > Please avoid sending me Word or PowerPoint attachments.
> > See http://www.gnu.org/philosophy/no-word-attachments.html
> > _______________________________________________
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> > Molpro-user at molpro.net
> > http://www.molpro.net/mailman/listinfo/molpro-user



-- 
*************************************************************
Jörg Saßmannshausen
Research Fellow
University of Strathclyde
Department of Pure and Applied Chemistry
295 Cathedral St.
Glasgow
G1 1XL

email: jorg.sassmannshausen at strath.ac.uk
web: http://sassy.formativ.net

Please avoid sending me Word or PowerPoint attachments.
See http://www.gnu.org/philosophy/no-word-attachments.html