Calculation of ESP charges with Molden

Calculation of ESP charges with Molden


Molden allows the calculation of charges fitted to the ElectroStatic Potential (ESP) on a series of connolly surfaces. (gamess/gaussian only). EXAMPLE:

      molden esp.test > esp.out
Where the contents of the file esp.test would be:

      esp test
      file = gaussian.test espch ptden=4.0 debug
Relevant keywords are:

      KEYWORDS:                                                Default
      ESPCH          triggers calculation esp charges
      NUMSURF=n      the number of connolly surfaces           (4)
      CONNSC=n.n     initial scalefactor vdwaals radii         (1.4)
      CONNINCR=n.n   increment scalefactor for next surface    (0.2)
      PTDEN=n.n      Density of points per Unit Area           (3.0)
      ARESP          Write out input files for the aresp program
      ISODEN         Fit the electrostatic potential on (3) isodensity
      DIPX=n.n       specifies dipole moment to be fitted to
      DIPY=n.n       specifies dipole moment to be fitted to
      DIPZ=n.n       specifies dipole moment to be fitted to
      The default is not to fit the dipole moment
      When constructing the atomspheres which make up the connolly surface, 
      use as principle axis :
      (sometimes necessary when you want to reproduce symmetry)
      AXIS-X,AXIS-Y,AXIS-Z                                     AXIS-Z
      After the calculation a file called "" is created, which can
      be read in by molden and charges can be displayed by clicking the label

After BESLER,MERZ,KOLLMAN J. COMPUT. CHEM. 11: 431-439; 1990

RESP is a program that will let you fit charges to multiple conformations. Resp is part of the antechamber suite of programs Download it here. When using the keyword ARESP molden will write out the resp input files: (containing the electrostatic potential) and (the resp keyword file) NOTE: Gaussian users not should forget to add the 6D gaussian input keyword to the gaussian input file.