Note
This website is presently under development. The primary website for MOPAC is still http://openmopac.net until the majority of its contents have been migrated here.
PMEPR¶
The Parametric Molecular Electrostatic Potential of Wang and
Ford [45,46]
is generated. When PMEPR is used, extra data must follow the
Z-matrix and symmetry data. This extra data defines the plane in which
the electrostatic potential is plotted, and is summarized in the Table.
Other keywords, e.g., MINMEP(to print the minima) or
PRTMEP(to write data for esplot to use) must be present.
Table: Data Required by PMEPR
Name of |
Allowed Values |
Datum |
|
ICASE |
1, 2, 3 |
N1 |
1-NUMAT |
N2 |
1-NUMAT, not N1 |
N3 |
1-NUMAT, not N1 or N2 |
X0 |
Any real number |
ICASE=1 If X0 is zero, then the plane generated passes through atoms
N1, N2 and N3. Obviously, these atoms should not lie on a
straight line. If X0 is non-zero, then the plane is parallel to the
plane of atoms N1, N2 and N3, but X0 Ångstroms above it.
ICASE=2 If X0 is zero, then the plane generated is perpendicular to
the plane of N1, N2 and N3, and includes the line from atom
N1 to N2. If X0 is non-zero, then the plane is perpendicular
to the plane of N1, N2 and N3, and is X0 Ångstroms
above, and parallel to, the line from atom N1 to N2.
ICASE=3 The plane used is that which bisects the angle
N2-N1-N3. X0 is meaningless in this context, and should
be set to zero.
Examples of extra data:
To generate data for the plane through atoms 10, 11, and 20, use as extra data: “1 10 11 20 0” (do not include the quotation marks.) Alternatively, every datum can be expressed in keyword style, as “icase=1 n1=10 n2=11 n3=20 z0=0”