Re: [cclib-devel] etsecs conversions

[Karol L. <kar...@kn...>]

On Tuesday 27 of March 2007 16:28, Noel O'Boyle wrote:
> On 27/03/07, Karol Langner <kar...@kn...> wrote:
> > Another note: jaguar prints the coefficients squared and doubled, just
> > like they were calculated by the Gaussian parser.
>
> Is the original sign included? If not, then it's obviously not
> possible to use the original 'unsquared' numbers.

I wrote too quickly... jaguar does something more: the original coefficients 
(read parser-wise the ones offered by GAMESS/Gaussian) are effecctively 
squared, doubled, square-rooted, and multiplied times the original sign.... 
that is, they are scaled by a factor of 2.0^0.5. Since alpha/beta electron 
excitations have the same sign for singlet states, it is possible to 
reproduce the original number.

The only question that remains is what do we want to put in etsecs in the end? 
Both alpha and beta excitations, even if they are not printed?

Karol

-- 
written by Karol Langner
Tue Mar 27 17:38:28 CEST 2007