Hi,
escf could be used in older versions with COSMO, because the keyword
was simply ignored. In this case, TDDFT is calculated on COSMO MOs, this
is the so-called slow term of the whole TDDFT/COSMO procedure. The
fast term was missing, but will be available (hopefully) soon.
In order to get a feeling about the order of magnitude we are dealing with,
here are some numbers calculated with a development version
of escf which includes the fast term:
The numbers are the 1. excitation energies of phenol (BP/SV(P) gas phase geometry)
calculated with BP/def2-SVPD (expt. value 4.51 eV).
A. = escf on gas phase MOs.
B. = escf on COSMO MOs.
C. = escf on COSMO MOs and TDDFT/COSMO fast term
# excitation energy / eV oscillator strength (length rep.)
A.: 0.47374991993630E+01 0.26480961196510E-01
B.: 0.47581682783343E+01 0.25674524688493E-01
C.: 0.47401835183371E+01 0.35611443906804E-01
There is just not much of a shift. There might be cases where the
effect is larger, but in practice, the largest effect will occur by going
from gas phase geometries to COSMO geometries.
Cheers,
Arnim