CHELP-SVD is now available at the Bryn Mawr College gopher
(gopher.brynmawr.edu). Look under Academic Departments/Chemistry/CHELP
Information regarding CHELP-SVD
Michelle Miller Francl
Lisa Emily Chirlian
Department of Chemistry
Bryn Mawr College
101 N. Merion Avenue
Bryn Mawr, PA 19010-2899
610 526 5108
CHELP-SVD is a copyrighted program. No part of it may be used in commercial
software without the express consent of the authors. Permission is granted to
copy and distribute this software under the constraints expressed above,
provided this copyright notice is
attached. Users are asked to reference the article describing CHELP-SVD when
describing work done with it or modified versions thereof.
This code is a modification of CHELP (Chirlian, L.E.; Francl, M.M. QCPE 1987,
7, 39). CHELP-SVD will find potential derived charges for molecules using as
input the molecular wavefunction. CHELP-SVD will do a preliminary fit,
determine the rank of the least squares matrix for the fit, select an
appropriate subset of atoms to which charges can be assigned based on that rank
estimate and then refit the selected set of charges.
A description of the methods incorporated into CHELP-SVD can be found in
"Charges Fit to Electrostatic Potentials II: Can Atomic Charges be
Unambiguously Fit to Electrostatic Potentials?" by C. Carey , L.E. Chirlian, D.
M. Gange and M.M. Francl which has been submitted to the Journal of
Computational Chemistry and "Charges Fit to Electrostatic Potentials", L.E.
Chirlian and M.M. Francl, J. Comp. Chem. 8, 894 (1987). An abstract of the
most recent paper is available on this gopher.