$PRTEFP group (optional) This group provides control for generating integer charge EFP fragments for constructing large EFPs. See P.A.Molina, H.Li, J.H.Jensen J.Comput.Chem. 24, 1971-1979 (2003) This group is mainly used in RUNTYP=MAKEFP runs. However, in MOPAC RUNTYP=ENERGY runs, the presence of a $PRTEFP group causes AM1 or PM3 charges to be printed and punched out in a suitable format for EFP calculations. NOPRT = an array specifying the atoms for which EFP multipole and polarizability points will not be printed/punched out. Example: For a molecule with the connectivity A1-A2-A3-A4-A5, NOPRT(1)=4,5 means that multipoles centered on atoms 4 and 5, and bond midpoints BO34 and BO45 are not part of the EFP. MIDPRT = an array specifying atoms whose bond midpoints neglected by using NOPRT should be printed out. Example: MIDPRT(1)=3 forces the printout of bond midpoint BO34. The neglect of monopoles leads to EFPs with overall non-integer charge. The next keyword defines "collection points" to which the removed monopoles are added. Thus, the net charge of the EFP=ICHARG. The presence of this "fictitious" charge is compensated for by adding an opposing dipole to the collection point. NUMFFD = an array that defines (1) a collection point, (2) the number of atoms contributing to monopoles to this point, and (3) the numbers of the atoms. More than one collection point can be defined. An opposing dipole is calculated as -0.5Q*r (Q = sum of neglected monopoles, r = distance between collection point and nearest neglected monopole) and placed at the collection point. Example: NUMFFD(1)=3,2,4,5. The sum of monopoles at A4, A5, BO34 and BO45 (Q) is added to the A3 monopole. A dipole, -0.5Q*r, is placed on A3, where r is the distance between A3 and BO34. If MIDPRT(1)=3, Q does not include the BO34 monopole, r is the distance between BO34 and A4, and the resulting dipole is centered on BO34. ========================================================== ==========================================================
generated on 7/7/2017