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Restrained point-charge models for disaccharides

Sigfridsson, E; Ryde, Ulf LU and Bush, BL (2002) In Journal of Computational Chemistry 23(3). p.351-364
Abstract
Various methods for deriving atomic partial charges from the quantum chemical electrostatic potential and moments have been tested for the sucrose molecule. We show that if no further information is used, the charges on some carbon atoms become large and charge patterns involving these atoms are badly determined and poorly transferable. Adding lone-pairs on the ether oxygen atoms or dividing the molecule into smaller fragments did not cure the instabilities. We develop a method, CHELP-BOW0, that restrains charges toward zero with different weights for different atoms. These harmonic restraints preserve the linear form of the least-squares equations, which are solved in a single step using singular-value decomposition. CHELP-BOW0 improves... (More)
Various methods for deriving atomic partial charges from the quantum chemical electrostatic potential and moments have been tested for the sucrose molecule. We show that if no further information is used, the charges on some carbon atoms become large and charge patterns involving these atoms are badly determined and poorly transferable. Adding lone-pairs on the ether oxygen atoms or dividing the molecule into smaller fragments did not cure the instabilities. We develop a method, CHELP-BOW0, that restrains charges toward zero with different weights for different atoms. These harmonic restraints preserve the linear form of the least-squares equations, which are solved in a single step using singular-value decomposition. CHELP-BOW0 improves the chemical transferability of the charges compared to unrestrained methods, and slightly improves their conformational transferability. It introduces a modest degradation of the fit compared to unrestrained CHELP-BOW (mean average deviation of the potential 0.00016 vs. 0.00010 a.u.). A second new method, CHELP-BOWC, avoids the need for restraints by including several conformations in the fit, weighting each according to its estimated energy in solution. CHELP-BOWC charges are more transferable than CHELP-BOW or CHELP-BOW0 charges to conformations not included in the training set. Restraints to zero charge do not further improve transferability of the CHELP-BOWC charges. We, therefore, recommend CHELP-BOW charges for rigid molecules and CHELP-BOWC charges for flexible molecules. (C) 2002 John Wiley Sons, Inc. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
rank-deficiency problems, restrained electrostatic potential charges, transferability, conformational, atomic charges, chemical transferability
in
Journal of Computational Chemistry
volume
23
issue
3
pages
351 - 364
publisher
John Wiley & Sons
external identifiers
  • wos:000173548700004
  • pmid:11908498
  • scopus:0036462494
ISSN
1096-987X
DOI
10.1002/jcc.10024
language
English
LU publication?
yes
id
12d603fd-1123-46bd-9b4c-5dd2f6b9d13f (old id 344121)
date added to LUP
2007-11-13 15:34:21
date last changed
2017-01-01 06:58:49
@article{12d603fd-1123-46bd-9b4c-5dd2f6b9d13f,
  abstract     = {Various methods for deriving atomic partial charges from the quantum chemical electrostatic potential and moments have been tested for the sucrose molecule. We show that if no further information is used, the charges on some carbon atoms become large and charge patterns involving these atoms are badly determined and poorly transferable. Adding lone-pairs on the ether oxygen atoms or dividing the molecule into smaller fragments did not cure the instabilities. We develop a method, CHELP-BOW0, that restrains charges toward zero with different weights for different atoms. These harmonic restraints preserve the linear form of the least-squares equations, which are solved in a single step using singular-value decomposition. CHELP-BOW0 improves the chemical transferability of the charges compared to unrestrained methods, and slightly improves their conformational transferability. It introduces a modest degradation of the fit compared to unrestrained CHELP-BOW (mean average deviation of the potential 0.00016 vs. 0.00010 a.u.). A second new method, CHELP-BOWC, avoids the need for restraints by including several conformations in the fit, weighting each according to its estimated energy in solution. CHELP-BOWC charges are more transferable than CHELP-BOW or CHELP-BOW0 charges to conformations not included in the training set. Restraints to zero charge do not further improve transferability of the CHELP-BOWC charges. We, therefore, recommend CHELP-BOW charges for rigid molecules and CHELP-BOWC charges for flexible molecules. (C) 2002 John Wiley Sons, Inc.},
  author       = {Sigfridsson, E and Ryde, Ulf and Bush, BL},
  issn         = {1096-987X},
  keyword      = {rank-deficiency problems,restrained electrostatic potential charges,transferability,conformational,atomic charges,chemical transferability},
  language     = {eng},
  number       = {3},
  pages        = {351--364},
  publisher    = {John Wiley & Sons},
  series       = {Journal of Computational Chemistry},
  title        = {Restrained point-charge models for disaccharides},
  url          = {http://dx.doi.org/10.1002/jcc.10024},
  volume       = {23},
  year         = {2002},
}