Dear Forum,
When relaxing water monomer and dimer and calculating their dipole moments
(everything done at the MP2 level, using the "cc-pVDZ" basis set for both O and H,
calculated with the ricc2 module), the ricc2 program reports the following values:
dipole moment for water monomer: >= 2.0 debye
dipole moment for water dimer: >= 3.0 debye
this is rubbish.. from literature, the correct (close to experiment) values are
~ 1.8D and 2.7D (see for example xantheas, jcp 102 11 (1995)).
I have tried also with
ricc2 -fanal
having the following lines in the control file:
$anadens
densityfile
where, as the densityfile, I have tried
mp2-gs1d-ur-1a-000.cao
mp2-gsdn-1a-000-total.cao
gsdens
ddens
the output from ricc2 (in the analysis mode) gives me always, in the case of
water dimer, dipole moments of ~ 3.0 debyes.
Have I completely missuderstood something here..?
Interestingly, those large dipole-moment values resemble the Hartree-Fock values.
It gets even better .. when I generate a file in the gaussian cube format and generate
the dipole moment using the information in that file (with a home-made program), i.e.
the electron density and the ionic positions and charges, I get much more reasonable
dipole moment values.
I attached a .zip file with control (you might want to remove the last, analysis-related lines), coordinates and
basis-set information.
Regards,
Sampsa