Re: [cclib-devel] mpenergies and GAMESS

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

On Friday 02 of March 2007 12:05, Noel O'Boyle wrote:
> Running ccget mpenergies on the GAMESS-US output files, we get:
>
> Attempting to parse water_ccd.out
> mpenergies:
> [ [-2073.99919009]]
> Attempting to parse water_ccsd(t).out
> mpenergies:
> [ [-2073.99919009]]
> Attempting to parse water_ccsd.out
> mpenergies:
> [ [-2073.99919009]]
> Attempting to parse water_mp2.out
> mpenergies:
> [ [-2040.91709961]]
>
> Should I be worried about the difference in the values? The reason I
> ask now, is that I am wondering whether to include this code (the code
> for parsing mpenergies from CC calculations) in the release branch.
>
> Noel

This difference is due to a difference in basis sets. Job water_mp2 uses 
STO-3G, while all the CC calculations were done for 6-31G(d,p). The problem 
is that GAMESS aborts if the number of correlating orbitals is smaller than 
the number of occupied ones (2 versus 4 for STO-3G). I'm not sure how 
critical this is from the chemical point of view, but Gaussian for instance 
has no problem with it (no warning).

Karol

-- 
written by Karol Langner
Fri Mar  2 17:54:53 CET 2007