A new ESP fitting algorithm

Hu, H., Lu, Z., and Yang, W.

Hao Hu, Zhenyu Lu, and Weitao Yang, Fitting Molecular Electrostatic Potentials from Quantum Mechanical Calculations,
Journal of Chemical Theory and Computation, 3 (3), 1004-1013, 2007.


1. Generate link-602 related files
2. Compile and link
3. Perform ESP fitting
All files provided here are for Gaussian03 Revision C.01/C.02, although I believe changing them to fit reversion D.01/D.02 is easy.

1. Generate link-602 related files
Download all files in a compressed tar file 602.tar.gz
There are three subroutines in l602.F that have been modified. They are "prop1e", "fitset", and "espfit", respectively.
There are also two new subroutines added to calculate grids and corresponding weights. They are "calweit.F" and "ldgrid.F".
To create the new link (still with the name l602), you need to
(a) create a directory, probably a subdirectory of g03.
(b) enter that directory, run "gau-fsplit $g03root/g03/l602.F" to generate all subroutines. Uncompress and extract files in 602.tar.gz.
(c) run "patch -p1" to apply patches "prop1e.patch", "fitset.patch", and "espfit.patch".

2. Compile and link
Use "$g03root/g03/bsd/updatelink1" to compile all Fortran files, including the two new files: "calweit.F" and "ldgrid.F". Link object files with proper libraries to generate executable l602.exe

3. ESP fitting
Now you can use this new l602.exe by specifying "%subst l602 this_new_directory" in your gaussian input file.
An example file "etoh.com" is also included in the tar file.

An explanation of this file is below
%NProc=2
%Mem=40MW
%Subst l602 /home/wychem/haohu/DEBUG/g03/MVESP/TEST/
#P B3Lyp/6-31G* Scf=Tight NoSymm Pop=chelpg
Iop(6/16=20,6/100=4,6/101=30,6/102=900,6/103=1000)

Ethanol

0 1
  6     1.172874   -0.410658    0.000000
  6     0.000000    0.555117    0.000000
  8    -1.199199   -0.214365    0.000000
  1    -1.947601    0.401530    0.000000
  1     0.051623    1.207767    0.887354
  1     0.051623    1.207767   -0.887354
  1     2.123182    0.135132    0.000000
  1     1.138759   -1.052016    0.886873
  1     1.138759   -1.052016   -0.886873
 ; Number of Processors
; Amount of memories
; alternative l602 executable
; Do ESP fitting. We use "pop=chelpg" to trigger the use of l602.exe.
; Iops used:
;   6/16:   accuracy
;   6/100: gridtype, 4 is for grids (75,302) and 5 is for (99,590)
;   6/101: Threshold for grid weights
;   6/102: rho_ref times 100.0
;   6/103: rho_sigma times 1000.0

Hao Hu
Revised: 05/01/07.