ADF COSMO calculation

Here it is described briefly how to make COSMO result files consistent with the way they were made for the ADF parametrization of COSMO-RS to ensure full parameter applicability. First a gas phase geometry optimization should be performed with ADF, with a TZP basis set, and the Becke-Perdew functional:

BASIS
type TZP
core Large
END
XC
GGA Becke Perdew
END

For heavy elements like iodine, a TZ2P basis set is required, including the relativistic scalar ZORA method. The resulting TAPE21 of the molecule (rename it compound_gasphase.t21) is used as a restart file in the COSMO calculation. The ADF COSMO calculation is performed with the following settings:

SYMMETRY NOSYM
SOLVATION
    SURF Delley
    DIV leb1=23 leb2=29 rleb=1.5
    SOLVENT name=CRS emp=0.0 cav0=0.0 cav1=0.0
    CHARGED method=CONJ conv=1e-10 iter=300 omega=1.0 corr
    C-Mat exact
    DISC sc=0.01 leg=4 tol=0.1
    RADII
       C   2.00
       H   1.30
       N   1.83
       O   1.72
       Cl  2.05
       F   1.72
       Br  2.16
       I   2.32
       Si  2.48
       P   2.13
       S   2.16
    SubEnd
END
XC
GGA Becke Perdew
END
RESTART compound_gasphase.t21

In this COSMO calculation the non-default Delley type of cavity construction is chosen (See Ref.[5] for details on the Delley surface construction). The name of the solvent is CRS, which sets the dielectric constant to infinite and sets the radius of the probing sphere to determine the solvent excluded part of the surface to 1.3 Angstrom. In the Radii subblock key the Klamt atomic cavity radii are chosen. The parameters emp, cav0, and cav1 are zero. The corr option to the CHARGED subkey constrains the computed solvent surface charges to add up to the negative of the molecular charge. Specifying exact for the C-MAT subkey causes ADF to compute straightforwardly the Coulomb potential due to the charge q in each point of the molecular numerical integration grid and integrate against the electronic charge density. This is, in principle, exact but may have inaccuracies when the numerical integration points are very close to the positions of a charge q. To remedy this, the point charges q are sometimes 'smeared out' and represented by a disc. Specifying exact for the C-MAT subkey also requires that the ADF calculation uses SYMMETRY NOSYM.

The resulting TAPE21 (rename it compound.t21) of the COSMO calculation is a COSMO result file.

In a COSMO-RS calculation only the 'COSMO' part of this file is needed. One can make a kf file compound.coskf, which only consists of the section 'COSMO' if one does:

$ADFBIN/cpkf compound.t21 compound.coskf "COSMO"

The file compound.coskf should not exist before this command is given. Note that such a .coskf file is not a complete TAPE21 anymore, and can not be viewed with ADFview, for example. It is only useful for COSMO-RS calculations.