Diffuse basis sets with COSMO model

[makochman]

Dear Turbomole Developers and Users,

I was wondering if it makes sense to use a basis set augmented with diffuse functions in an MP2/ADC(2) calculation using COSMO. My guess is yes, provided that the reaction field is not being equilibrated with an electronic state with a pronounced diffuse character, for example, a Rydberg-type π3s state of an organic molecule.

The reason I would like to know this is that I performed some gas-phase calculations for a fluorescent molecule which has several low-lying excited states, among them a π3s-type state. I used the MP2/ADC(2)/aug-cc-pVDZ level of theory. I would like to know how equilibrium solvation stabilizes the emissive (ππ*-type) electronic state relative to the ground state and the other electronic states. For the sake of consistency with the gas phase calculations, I would like to keep using the aug-cc-pVDZ basis set if possible.

Thank you for any advice and suggestions,

Michal Kochman

Postdoctoral researcher
Max Planck Institute for the Structure and Dynamics of Matter (MPSD)
Hamburg, Germany

[Arnim]

Hi,

in principle, any basis set can be used with COSMO.
Diffuse functions might lead to larger values for the outlying charge correction. But other errors should be larger.

Best,

Arnim