[molpro-user] Radical Cation Wavefunction

[MD Simulation]

Hi Joachim,

Thanks for your reply, it's very helpful.

How do I know the state symmetry before the calculation?  I would like to
read more about how to determine the proper symmetry, are there specific
terms I could look up for the wave function symmetry?

I've read this section of the quickstart manual several times:
https://www.molpro.net/info/2012.1/doc/quickstart/node11.html
I've also read:

https://www.molpro.net/info/2012.1/doc/manual/node33.html#sec:symmetry
https://www.molpro.net/info/2012.1/doc/manual/node34.html


Again, thank you for your help,
Alan




On Sat, Apr 16, 2016 at 6:27 AM, Hans-Joachim Werner <
werner at theochem.uni-stuttgart.de> wrote:

> Hi,
> the Hartree-Fock program at least tries to find the lowest state and to
> determine the state symmetry automatically. But this is based on orbital
> energies and there
> is no guarantee that the correct state is always found. The meaning of the
> state symmetries is explained in the manual, see also the quickstart manual
> for examples. For example, in a linear molecule oriented along the z-axis,
> a Sigma^+, state has symmetry 1, Pi_x, Pi_y (symmetries 2,3), Sigma^-
> symmetry 4, Delta_{x^2-y^2} symmetry 1, Delta_{xy} symmetry 4 (but note
> that some of these states require more than 1 Slater determinant, and then
> mcscf muust be used for a proper description).
> Best regards
> Joachim Werner
> ---
> Prof. Dr. Hans-Joachim Werner
> Institute for Theoretical Chemistry
> University of Stuttgart
> Pfaffenwaldring 55
> D-70569 Stuttgart
> Tel: +49 711 / 685 64400
> Fax: +49 711 / 685 64442
> email: werner at theochem.uni-stuttgart.de
>
>
> > Am 15.04.2016 um 14:56 schrieb MD Simulation <
> mdsimulationgroup at gmail.com>:
> >
> > Hello Molpro Users,
> >
> > I'm very new Molpro but have used NWChem and Gaussian quite a bit.  I'm
> attempting to use CCSD(T) on a radical cation organic compound.  My
> question is, how necessary is it to set the wavefunction symmetry and
> occupied orbitals (I'm not certain how to determine either of those) in the
> WF card and OCC card?  In NWChem or Gaussian I would simply set the charge
> (equal to 1) and multiplicity (equal to 2), so in this case will I get the
> correct results by simply using:
> >
> > """
> > wf,charge=1,spin=1
> > """
> >
> > Thanks for the help.  And as a side note, Molpro is really fast!
> >
> > Cheers,
> > Alan
> > _______________________________________________
> > Molpro-user mailing list
> > Molpro-user at molpro.net
> > http://www.molpro.net/mailman/listinfo/molpro-user
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.molpro.net/pipermail/molpro-user/attachments/20160416/40322b38/attachment.html>