[molpro-user] CCSD convergence criteria & restart

[Daniel Svozil]

Hi all,

I am trying to understand when CCSD is considered to be converged.
According to manual
(http://www.molpro.net/info/current//doc/manual/node322.html) 

"The convergence thresholds can be modified using

THRESH,ENERGY=thrden,COEFF=thrvar

Convergence is reached if the energy change is smaller than thrden
(default 1.d-6) and the square sum of the amplitude changes is smaller
than thrvar (default (1.d-10)."

What are amplitude changes? VAR(S) and VAR(P)? And what those variables
actually mean? Change in sibles and pairs energies? 
There is also global directive GTHRESH, where COEFF key
means "Convergence threshold for coefficients in CI and CCSD (default 1.d-4)" 
(http://www.molpro.net/info/current//doc/manual/node62.html#command:gthresh),
but this is apparently different that what is said at CCSD THRESH manual
page. And moreover it seems to me, that the implicit value of COEFF is
1.d-5. How to print out CCSD coefficients to the output file? I have
very slowly converging dipole-bound anion and I would like to relax
convergence criteria, the energy change is negligible and constant 
(1d-8), but the job doesn't stop here.

Also, is it possible to restart CCSD calculation from the last already
done iteration (for both open (rsscd(t)) and closed shell systems)? When
I write int and wfu files and I use them in the next run, only HF
reference is restarted, but not CCSD.

Thanks in advance
  Dan

-- 
Daniel Svozil, PhD
Institute of Organic Chemistry and Biochemistry
and Center for Complex Molecular Systems and Biomolecules
http://www.molecular.cz/
Czech Republic

phone: +420-220 410 313

----- End forwarded message -----

-- 
Daniel Svozil, PhD
Institute of Organic Chemistry and Biochemistry
and Center for Complex Molecular Systems and Biomolecules
http://www.molecular.cz/
Czech Republic

phone: +420-220 410 313