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Comparison of methods for deriving atomic charges from the electrostatic potential and moments

Sigfridsson, Emma LU and Ryde, Ulf LU (1998) In Journal of Computational Chemistry 19(4). p.377-395
Abstract

Four methods for deriving partial atomic charges from the quantum chemical electrostatic potential (CHELP, CHELPG, Merz-Kollman, and RESP) have been compared and critically evaluated. It is shown the charges strongly depend on how and where the potential points are selected. Two alternative methods are suggested to avoid the arbitrariness in the point-selection schemes and van der Waals exclusion radii: CHELP-BOW, which also estimates the charges from the electrostatic potential, but with potential points that are Boltzmann-weighted after their occurrence in actual simulations using the energy function of the program in which the charges will be used, and CHELMO, which estimates the charges directly from the electrostatic multipole... (More)

Four methods for deriving partial atomic charges from the quantum chemical electrostatic potential (CHELP, CHELPG, Merz-Kollman, and RESP) have been compared and critically evaluated. It is shown the charges strongly depend on how and where the potential points are selected. Two alternative methods are suggested to avoid the arbitrariness in the point-selection schemes and van der Waals exclusion radii: CHELP-BOW, which also estimates the charges from the electrostatic potential, but with potential points that are Boltzmann-weighted after their occurrence in actual simulations using the energy function of the program in which the charges will be used, and CHELMO, which estimates the charges directly from the electrostatic multipole moments. Different criteria for the quality of the charges are discussed. The CHELMO method gives the best multipole moments for small and medium-sized polar systems, whereas the CHELP-BOW charges reproduce best the total interaction energy in actual simulations. Among the standard methods, the Merz-Kollman charges give the best moments and potentials, but they show an appreciable dependence on the orientation of the molecule. We have also examined the recent warning that charges derived by a least-squares fit to the electrostatic potential normally are not statistically valid. It is shown that no rank-deficiency problems are encountered for molecules with up to 84 atoms if the least-squares fit is performed using pseudoinverses calculated by singular value decomposition and if constraints are treated by elimination. © 1998 John Wiley & Sons, Inc.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Atomic charges, Copper complexes, Electrostatic potential charges, Molecular simulation, Rank-deficiency problems
in
Journal of Computational Chemistry
volume
19
issue
4
pages
19 pages
publisher
John Wiley & Sons
external identifiers
  • scopus:11644300961
ISSN
0192-8651
DOI
10.1002/(SICI)1096-987X(199803)19:4<377::AID-JCC1>3.0.CO;2-P
language
English
LU publication?
yes
id
48cac792-da30-421f-a2c3-00f750c99357
date added to LUP
2017-02-04 11:36:46
date last changed
2017-09-24 05:06:46
@article{48cac792-da30-421f-a2c3-00f750c99357,
  abstract     = {<p>Four methods for deriving partial atomic charges from the quantum chemical electrostatic potential (CHELP, CHELPG, Merz-Kollman, and RESP) have been compared and critically evaluated. It is shown the charges strongly depend on how and where the potential points are selected. Two alternative methods are suggested to avoid the arbitrariness in the point-selection schemes and van der Waals exclusion radii: CHELP-BOW, which also estimates the charges from the electrostatic potential, but with potential points that are Boltzmann-weighted after their occurrence in actual simulations using the energy function of the program in which the charges will be used, and CHELMO, which estimates the charges directly from the electrostatic multipole moments. Different criteria for the quality of the charges are discussed. The CHELMO method gives the best multipole moments for small and medium-sized polar systems, whereas the CHELP-BOW charges reproduce best the total interaction energy in actual simulations. Among the standard methods, the Merz-Kollman charges give the best moments and potentials, but they show an appreciable dependence on the orientation of the molecule. We have also examined the recent warning that charges derived by a least-squares fit to the electrostatic potential normally are not statistically valid. It is shown that no rank-deficiency problems are encountered for molecules with up to 84 atoms if the least-squares fit is performed using pseudoinverses calculated by singular value decomposition and if constraints are treated by elimination. © 1998 John Wiley &amp; Sons, Inc.</p>},
  author       = {Sigfridsson, Emma and Ryde, Ulf},
  issn         = {0192-8651},
  keyword      = {Atomic charges,Copper complexes,Electrostatic potential charges,Molecular simulation,Rank-deficiency problems},
  language     = {eng},
  number       = {4},
  pages        = {377--395},
  publisher    = {John Wiley & Sons},
  series       = {Journal of Computational Chemistry},
  title        = {Comparison of methods for deriving atomic charges from the electrostatic potential and moments},
  url          = {http://dx.doi.org/10.1002/(SICI)1096-987X(199803)19:4<377::AID-JCC1>3.0.CO;2-P},
  volume       = {19},
  year         = {1998},
}