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Re^2: Calculation of solvation energy including CAV and DISREP

Alex Granovsky
gran@classic.chem.msu.su


Hi again,

one more comment: values in DKA and RWA arrays should be entered for
every atom according to the atom numbering scheme of the expanded $data
group (i.e., they are given for atoms, not for atom types!)
The maximum number of atoms you can enter is 50.

Regards,
Alex Granovsky



On Wed Oct 12 '11 7:04pm, Alex Granovsky wrote
----------------------------------------------
>Hi Patrick,

>>When ICAV=1 and SOLVENT=WATER, is it necessary to enter the values for TCE, VMOL, STEN, DSTEN and CMF in the input file?

>For built-in solvents you do not need to enter anything. According to documentation, the only relevant parameter is:

>
>            If ICAV=1, the following parameter is relevant:

>          TABS   = the absolute temperature, in units K.
>                   (default=298.0)
>

>
>
>>When IDISP=1 and SOLVENT=WATER, is it necessary to enter the values for RHO,N, NT, RDIFF, DK and RW in the input file?

>
>          $DISREP group

>             This group controls evaluation of the dispersion and
>          repulsion energies by the empirical method of Floris and
>          Tomasi.  The group must be given with IDISP=1 in $PCM.
>          The two options are controlled by ICLAV and ILJ, only one
>          of which should be selected.

>          ICLAV = selects Claverie's disp-rep formalism.
>                = 0 skip computation.
>                = 1 Compute the solute-solvent disp-rep interaction
>                    as a sum over atom-atom interactions through a
>                    Buckingham-type formula (R^-6 for dispersion,
>                    exp for repulsion).  (default)
>                    Ref: Pertsin-Kitaigorodsky "The atom-atom
>                         potential method", page 146.

>          ILJ   = selects a Lennard-Jones formalism.
>                = 0 skip computation. (default)
>                = 1 solute atom's-solvent molecule interaction is
>                    modeled by Lennard-Jones type potentials, R^-6
>                    for dispersion, R^-12 for repulsion).

>          ---- the following data must given for ICLAV=1:

>          RHO   = solvent numeral density
>          N     = number of atom types in the solvent molecule
>          NT    = an array of the number of atoms of each type in a
>                  solvent molecule
>          RDIFF = distances between the first atoms of each type
>                  and the cavity
>          DKT,RWT = parameters of atom-atom interactions (solvent)
>          DKA,RWA = parameters of atom-atom interactions (solute)
>
>
>          The defaults are chosen for water,
>             RHO=3.348D-02
>             N=2
>             NT(1)=2,1
>             RDIFF(1)=1.20,1.50
>             DKT(1)=1.0,1.36
>             RWT(1)=1.2,1.5

>          ---- the following data must given for ILJ=1:

>          RHO   = solvent numeral density
>          EPSI  = an array of energy constants referred to each atom
>                  of the solute molecule.
>          SIGMA = an array of typical distances, relative to each
>                  solute atom

>

>Thus, for water as solvent you need to enter only DKA and RWA arrays.

>Hope this helps.

>Regards,
>Alex Granovsky

>On Fri Oct 7 '11 2:56am, Patrick SK Pang wrote
>----------------------------------------------
>>I used the following input to calculate the solvation energy.
>> $CONTRL RUNTYP=Energy $END
>> $CONTRL SCFTYP=RHF MAXIT=200 $END
>> $CONTRL ICHARG=0  MULT=1 $END
>> $SCF DIRSCF=.TRUE. NCONV=9 $END
>> $P2P P2P=.T. DLB=.T. $END
>> $SYSTEM TIMLIM=3000 MWORDS=100 $END
>> $BASIS EXTFIL=.T. GBASIS=cc-pvdz $END
>> $PCM SOLVNT=WATER ICAV=1 IDISP=1 $END
>> $DISREP ICLAV=1 $END
>> $DATA
>>Molecule specification

>>When ICAV=1 and SOLVENT=WATER, is it necessary to enter the values for TCE, VMOL, STEN, DSTEN and CMF in the input file?

>>When IDISP=1 and SOLVENT=WATER, is it necessary to enter the values for RHO,N, NT, RDIFF, DK and RW in the input file?

>>I got the zero dispersion free energy and repulsion free energy. Are there any mistakes in the input file?
>> � � � � � � ----------------------------------------------
>> � � � � � � ------- � RESULTS OF PCM CALCULATION � -------
>> � � � � � � ----------------------------------------------

>> FREE ENERGY IN SOLVENT = � � � = � �-1917.4382855787 A.U.
>> INTERNAL ENERGY IN SOLVENT = � � � = � �-1917.3934872440 A.U.
>> DELTA INTERNAL ENERGY = � � � � = � � � �0.0000000000 A.U.
>> ELECTROSTATIC INTERACTION = 1/2(PB+PC) + 1/2PX + UNZ= � � � -0.0447983346 A.U.
>> PIEROTTI CAVITATION ENERGY � � � � � � � � � � � � �= � � � �0.1118759048 A.U.
>> DISPERSION FREE ENERGY � � � � � � � � � � � � � � �= � � � �0.0000000000 A.U.
>> REPULSION FREE ENERGY � � � � � � � � � � � � � � � = � � � �0.0000000000 A.U.
>> TOTAL INTERACTION (DELTA + ES + CAV + DISP + REP) � = � � � �0.0670775701 A.U.
>> TOTAL FREE ENERGY IN SOLVENT � � � � � � � � � � � �= � �-1917.3264096739 A.U.
>>


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