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$EFPARM group (optional, experimental)
This group is designed to set additional parameters affecting EFP calculation.
As of now, it contains the following keys:
CTCUT is an array of floating-point values setting the cutoff radii
for each pair of EFP fragment types, interpreted as a
lower-triangular column-major matrix. Nonnegative value sets a
cutoff in Bohr units, irrespective of the value of UNITS in
$CONTRL group. Negative value is interpreted as "no cutoff" (or
"infinite cutoff").
Currently, gradients are not available for the EFP-with-cutoffs.
Example:
Suppose, the EFP system contains 8 fragments: first 3 of type
AAA, then 2 of type BBB, then 3 of type CCC. Then the input is
interpreted this way:
CTCUT(1)= AAA-AAA, AAA-BBB, BBB-BBB, AAA-CCC, BBB-CCC, CCC-CCC
where III-JJJ is a cutoff radius between fragments of type III
and JJJ.
End of example.
==========================================================
$FRAGNAME group
(required for each FRAGNAME given in $EFRAG)
This group gives all pertinent information for a given
Effective Fragment Potential (EFP). This information falls
into three categories, with the first two shared by the
EFP1 and EFP2 models:
electrostatics (distributed multipoles, screening)
polarizability (distributed dipole polarizabilities)
The EFP1 model contains one final term,
fitted exchange repulsion
whereas the EFP2 model contains a collection of terms,
exchange repulsion, dispersion, charge transfer...
An Effective Fragment Potential is input using several
different subgroups. Each subgroup is specified by a
particular name, and is terminated by the word STOP. You
may omit any of the subgroups to omit that term from the
EFP. All values are given in atomic units.
To input monopoles, follow input sequence -EM-
To input dipoles, follow input sequence -ED-
To input quadrupoles, follow input sequence -EQ-
To input octopoles, follow input sequence -EO-
To input electrostatic screening, follow input seq. -ES-
To input polarizable points, follow input sequence -P-
To input polarizability screening, follow input seq. -PS-
To input fitted "repulsion", follow input sequence -R-
To input Pauli exchange, follow input sequence -PE-
To input dispersion, follow input sequence -D-
To input charge transfer, follow input sequence -CT-
The data contained in a $FRAGNAME is normally generated by
performing a RUNTYP=MAKEFP using a normal $DATA's ab initio
computation on the desired solvent molecule. A MAKEFP run
will generate all terms for an EFP2 potential, including
multipole screening parameters. The screening option is
controlled by $DAMP and $DAMPGS input, and by you checking
the final fitting parameters for reasonableness.
Note that the ability to fit the "repulsion" term in an
EFP1 potential is not included in GAMESS, meaning that EFP1
computations normally use built-in EFP1 water potentials.
----------------------------------------------------------
-1- a single descriptive title card
----------------------------------------------------------
-2- COORDINATES
COORDINATES signals the start of the subgroup containing
the multipolar expansion terms (charges, dipoles, ...).
Optionally, one can also give the coordinates of the
polarizable points, or centers of exchange repulsion.
-3- NAME, X, Y, Z, WEIGHT, ZNUC
NAME is a unique string identifying the point.
X, Y, Z are the Cartesian coordinates of the point, and
must be in Bohr units.
WEIGHT, ZNUC are the atomic mass and nuclear charge, and
should be given as zero only for points which are
not nuclei.
In EFP1 potentials, the true nuclei will appear twice, once
for defining the positive nuclear charge and its screening,
and a second time for defining the electronic distributed
multipoles.
Repeat line -3- for each expansion point, and terminate
the list with a "STOP".
----------------------------------------------------------
Note: the multipole expansion produced by RUNTYP=MAKEFP
comes from Stone's distributed multipole analysis (DMA).
An alternative expansion, from a density based multipole
expansion (DBME) performed on an adaptive grid is placed in
the job's PUNCH file. This alternative multipole expansion
may be preferable if large basis sets are in use (the DMA
expansion is basis set sensitive). The DBME values can be
inserted in place of the DMA values, for -EM-, -ED, -EQ-,
and -EO- sections, if you wish. Experience suggests that
DBME multipoles are about as accurate as those obtained
using DMA.
-EM1- MONOPOLES
MONOPOLES signals the start of the subgroup containing
the electronic and nuclear monopoles.
-EM2- NAME, CHARGE1, CHARGE2
NAME must match one given in the COORDINATES subgroup.
CHARGE1 = electronic monopole at this point.
CHARGE2 = nuclear monopole at this point. Omit or enter
zero if this is a bond midpoint or some other
expansion point that is not a nucleus.
Repeat -EM2- to define all desired charges.
Terminate this subgroup with a "STOP".
----------------------------------------------------------
-ED1- DIPOLES
DIPOLES signals the start of the subgroup containing the
dipolar part of the multipolar expansion.
-ED2- NAME, MUX, MUY, MUZ
NAME must match one given in the COORDINATES subgroup.
MUX, MUY, MUZ are the components of the electronic dipole.
Repeat -ED2- to define all desired dipoles.
Terminate this subgroup with a "STOP".
----------------------------------------------------------
-EQ1- QUADRUPOLES
QUADRUPOLES signals the start of the subgroup containing
the quadrupolar part of the multipolar expansion.
-EQ2- NAME, XX, YY, ZZ, XY, XZ, YZ
NAME must match one given in the COORDINATES subgroup.
XX, YY, ZZ, XY, XZ, and YZ are the components of the
electronic quadrupole moment.
Repeat -EQ2- to define all desired quadrupoles.
Terminate this subgroup with a "STOP".
----------------------------------------------------------
-EO1- OCTUPOLES (note: OCTOPOLES is misspelled)
OCTUPOLES signals the start of the subgroup containing
the octupolar part of the multipolar expansion.
-EO2- NAME, XXX, YYY, ZZZ, XXY, XXZ,
XYY, YYZ, XZZ, YZZ, XYZ
NAME must match one given in the COORDINATES subgroup.
XXX, ... are the components of the electronic octopole.
Repeat -EO2- to define all desired octopoles.
Terminate this subgroup with a "STOP".
----------------------------------------------------------
-ES1a- SCREEN
SCREEN signals the start of the subgroup containing
Gaussian screening (A*exp[-B*r**2]) for the distributed
multipoles, which account for charge penetration effects.
SCREEN pertains to ab initio-EFP multipole interactions, in
contrast to the SCREENx groups defined just below for EFP-
EFP interactions.
-ES1b- NAME, A, B
NAME must match one given in the COORDINATES subgroup.
A, B are the parameters of the Gaussian screening term.
Repeat -ES1b- to define all desired screening points.
Terminate this subgroup with a "STOP".
----------------------------------------------------------
note: SCREENx input (any x) is only obeyed if ISCRELEC=0.
SCREENx input will be ignored if ISCRELEC=1.
One (and only one) of the following groups should appear to
define the EFP-EFP multipole screening:
-ES2a- SCREEN1 or SCREEN2 or SCREEN3
SCREEN1 signals the start of the subgroup containing
Gaussian screening (A*exp[-B*r**2]) for the distributed
multipoles, which account for charge-charge penetration
effects.
SCREEN2 signals the start of the subgroup containing
exponential screening (A*exp[-B*r]) for the distributed
multipoles, which account for charge-charge penetration
effects. This is often the EFP-EFP screening of choice.
SCREEN3 signals the start of the subgroup containing the
screening terms (A*exp[-B*r]) for the distributed
multipoles, which account for high-order penetration
effects (higher terms means charge-charge, as for SCREEN1
or SCREEN2, but also charge-dipole, charge-quadrupole, and
dipole-dipole and dipole-quadrupole terms).
-ES2b- NAME, A, B
NAME must match one given in the COORDINATES subgroup.
A, B are the parameters of the exponential screening term.
Repeat -ES2b- to define all desired screening points.
Terminate this subgroup with a "STOP".
----------------------------------------------------------
-P1- POLARIZABLE POINTS
POLARIZABLE POINTS signals the start of the subgroup
containing the distributed dipole polarizability tensors,
and their coordinates. This subgroup allows the
computation of the polarization energy.
-P2- NAME, X, Y, Z
NAME gives a unique identifier to the location of this
polarizability tensor. It might match one of the points
already defined in the COORDINATES subgroup, but often does
not. Typically the distributed polarizability tensors are
located at the centroids of localized MOs.
X, Y, Z are the coordinates of the polarizability point.
They should be omitted if NAME did appear in COORDINATES.
The units are controlled by UNITS= in $CONTRL.
-P3- XX, YY, ZZ, XY, XZ, YZ, YX, ZX, ZY
XX, ... are components of the distributed polarizability,
which is not a symmetric tensor. XY means dMUx/dFy, where
MUx is a dipole component, and Fy is a component of an
applied field.
Repeat -P2- and -P3- to define all desired polarizability
tensors, and terminate this subgroup with a "STOP".
----------------------------------------------------------
-PS1- POLSCR
This section must not be given if ISCRPOL=1. If not given,
when ISCRPOL=0, no polarization screening is performed.
POLSCR signals the start of the subgroup containing the
screening (by exp[-B*r]) for the induced dipoles. It
pertains only to EFP-EFP interactions. It requires that
you be using SCREEN3 damping of the multipole-multipole
interactions! It applies to charge/induced dipole,
dipole/induced dipole, quadrupole/induced dipole, and
induced dipole/induced dipole terms.
-PS2- NAME, B
NAME must match one of the distributed dipole points given
in the POLARIZABLE subgroup.
B is the exponent of the exponential screening term, and a
typical value is about 1.5.
Repeat -PS2- to define all desired screening points.
Terminate this subgroup with a "STOP".
----------------------------------------------------------
FORCE POINT
This section controls coarse graining of the gradient, if
FRCPNT is selected in $EFRAG. The input consists of the
coordinates of the desired points:
COM x y z
FP1 x y z
FP2 x y x
...
STOP
where x,y,z are the coordinates of center of mass (COM) and
also any desired "force points" FP1, FP2, ...
Terminate this subgroup with a "STOP".
----------------------------------------------------------
EFP1 versus EFP2
The EFP1 model consists of a fitted potential, which is a
remainder term, after taking care of electrostatics and
polarization with the input described above. The fitted
term is called a "repulsive potential" because its largest
contribution stems from Pauli exchange repulsion. The fit
actually contains several other interactions, since it is
just a fit to the total interaction potential's remainder
after subtracting the elecrostatic and polarization
interactions.
The EFP2 model uses analytic representations for exchange
repulsion and other terms, and these are documented after
the EFP1's "repulsive potential".
----------------------------------------------------------
-R1- REPULSIVE POTENTIAL
See also the $FRGRPL input group, which defines the fit for
the EFP1-EFP1 repulsion term.
REPULSIVE POTENTIAL signals the start of the subgroup
containing the fitted exchange repulsion potential, for the
interaction between the fragment and the ab initio part of
the system. This term also accounts, in part, for other
effects, since it is a fit to a remainder. The fitted
potential has the form
N
sum C * exp[-D * r**2]
i i i
-R2- NAME, X, Y, Z, N
NAME may match one given in the COORDINATES subgroup, but
need not. If NAME does not match one of the known points,
you must give its coordinates X, Y, and Z, otherwise omit
these three values. N is the total number of terms in the
fitted repulsive potential.
-R3- C, D
These two values define the i-th term in the repulsive
potential. Repeat line -R3- for all N terms.
Repeat -R2- and -R3- to define all desired repulsive
potentials, and terminate this subgroup with a "STOP".
----------------------------------------------------------
The following terms are part of the developing EFP2 model.
This model replaces the "kitchen sink" fitted repulsion in
the EFP1 model by analytic formulae. These formulae are to
be specific for each kind of physical interaction, and to
pertain to any solvent, not just water. The terms which
are programmed so far are given below.
----------------------------------------------------------
-PE1- PROJECTION BASIS SET
-PE2- PROJECTION WAVEFUNCTION n m
-PE3- FOCK MATRIX ELEMENTS
-PE4- LMO CENTROIDS
These four sections contain the data needed to compute the
Pauli exchange repulsion, namely
1. the original basis set used to extract the potential.
2. the localized orbitals, expanded in that basis.
3. the Fock matrix, in the localized orbital basis.
4. the coordinates of the center of each localized orb.
The information generated by a MAKEFP that follows these
four strings is largely self explanatory. Note, however,
that the orbitals (PE2) must have two integers giving the
number of occupied orbitals -n- and the size of the basis
set -m-. The PE2 and PE3 subsections do not contain STOP
lines.
----------------------------------------------------------
-D1- DYNAMIC POLARIZABLE POINTS
DYNAMIC POLARIZABLE POINTS signals the start of the
subgroup containing the distributed imaginary frequency
dipole polarizability tensors, and their coordinates. This
information permits the computation of dispersion energies.
-D2- NAME, X, Y, Z
NAME gives a unique identifier to the location of this
polarizability tensor. It might match one of the points
already defined in the COORDINATES subgroup, but often does
not. Typically the distributed polarizability tensors are
located at the centroids of localized MOs.
X, Y, Z are the coordinates of the polarizability point.
They should be omitted if NAME did appear in COORDINATES.
The units are controlled by UNITS= in $CONTRL.
-D3- XX, YY, ZZ, XY, XZ, YZ, YX, ZX, ZY
XX, ... are components of the distributed polarizability,
which is not a symmetric tensor. XY means dMUx/dFy, where
MUx is a dipole component, and Fy is a component of an
applied field.
Repeat -D2- and -D3- to define all desired polarizability
tensors, and then repeat for all desired imaginary
frequencies. MAKEFP jobs use 12 imaginary frequencies at
certain internally stored values, to enable quadrature of
these tensors, to form the C6 dispersion coefficient. Thus
D2 and D3 input is repeated 12 times. Terminate this
subgroup with a "STOP".
----------------------------------------------------------
-QD1- DIPOLE-QUADRUPOLE DYNAMIC POLARIZABLE POINTS
-QD2- data similar to -D2- above
-QD3- data similar to -D3- above
These data are used for the 7th power dispersion formula,
and are already in the right format from a MAKEFP run. See
also NODISP7 above, to skip its use.
----------------------------------------------------------
-CT1- CTVEC n m
-CT2- CTFOK
These two sections contain the data needed to compute the
charge transfer energy, namely
1. the canonical occupied orbitals, followed by either
valence virtuals or canonical virtuals, depending on
CTVVO's setting during the MAKEFP run. These MOs are
expanded in the -PE1- basis.
2. the occupied orbitals' eigenvalues.
The information generated by a MAKEFP that follows these
two strings is largely self explanatory. The MO and AO
sizes given by -n- and -m- have the same meaning as for the
-PE2- group. The CTVEC info does not have a STOP line, but
CTFOK does.
----------------------------------------------------------
The EFP2 model presently can generate the energy for a
system with an ab initio molecule and EFP2 solvents, if
only Pauli exchange repulsion is used. The AI-EFP gradient
for this term is not yet programmed, nor are there AI-EFP
codes for dispersion or charge transfer. Thus use of the
EFP2 model, for all practical purposes, is limited to EFP-
EFP interactions only, via COORD=FRAGONLY.
==========================================================
generated on 7/7/2017