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DCCOSMO-RS:

The DCOSMO-RS model (see chapter 17) has been implemented for restricted and unrestricted DFT and HF energy calculations and gradients (programs: dscf/ridft and grad/rdgrad). In addition to the COSMO settings defined at the beginning of this section, the $dcosmo_rs keyword has to be set.
$dcosmo_rs file=filename.pot

activates the DCOSMO-RS method. The file defined in this option contains the DCOSMO-RS σ -potential and related data (examples can be found in the default potentials in the $TURBODIR/parameter directory).
If the potential file cannot be found in the local directory of the calculation, it will be searched in the $TURBODIR/parameter directory. The following σ -potential files for pure solvents at 25 oC are implemented in the current TURBOMOLE distribution (see parameter subdirectory):
Water:
h2o_25.pot
Ethanol:
ethanol_25.pot
Methanol:
methanol_25.pot
Tetrahydrofurane:
thf_25.pot
Acetone:
propanone_25.pot
Chloroform:
chcl3_25.pot
Tetrachloromethane:
ccl4_25.pot
Acetonitrile:
acetonitrile_25.pot
Nitromethane:
nitromethane_25.pot
Dimethylsulfoxide:
dimethylsulfoxide_25.pot
Diethylether:
diethylether_25.pot
Hexane:
hexane_25.pot
Cyclohexane:
cyclohexane_25.pot
Benzene:
benzene_25.pot
Toluene:
toluene_25.pot
Aniline:
aniline_25.pot
The DCOSMO-RS energies and total charges are listed in the COSMO section of the output:
  SCREENING CHARGE:
    cosmo      :  -0.012321
    correction :   0.011808
    total      :  -0.000513
 (correction on the COSMO level)
  ENERGIES [a.u.]:
    Total energy            =      -76.4841708454
    Outlying charge corr. (COSMO)    =    -0.0006542315
    Outlying charge corr. (DCOSMO-RS)=    -0.0011042856
    Combinatorial contribution of the solute =    -0.0017627889
    (at inf. dil. in the mixture/pure solvent. Not included in the total energy above)
The outlying charge correction cannot be defined straight forward like in the normal COSMO model. Therefore, the output shows two corrections that can be added to the Total energy. The first one is the correction on the COSMO level (COSMO) and the second is the difference of the DCOSMO-RS dielectric energy calculated form the corrected and the uncorrected COSMO charges, respectively (DCOSMO-RS). The charges are corrected on the COSMO level only. The Total energy includes the Ediel, RS defined in section 17. Additionally the combinatorial contribution at infinite dilution of the COSMO-RS model is given in the output. The use of this energy makes sense if the molecule under consideration is different than the used solvent or not component of the solvent mixture, respectively. To be consistent one should only compare energies containing the same contributions, i.e. same outlying charge correction and with or without combinatorial contribution. Please note: the COSMO-RS contribution of the DCOSMO-RS energy depends on the reference state and the COSMO-RS parameterization (used in the calculation of the chosen COSMO-RS potential). Therefore, the DCOSMO-RS energies should not be used in a comparison with the gas phase energy, i.e. the calculation of solvation energies.
next up previous contents index
Next: Keywords for Modules Grad Up: Keywords for Cosmo Previous: COSMO in vertical excitations   Contents   Index
TURBOMOLE M