Theoretical characterization of oxoanion, XOm n-, solvation

Donald M. Camaioni, Michel Dupuis, John Bentley

Research output: Contribution to journalArticle

34 Citations (Scopus)

Abstract

We describe a new cavity definition protocol that yields accurate solvation energies and electrode potentials for selected oxoanions, XOm n-, including some for which other cavity protocols do not perform well enough. In this new definition scheme with cavities made of interlocked atomic spheres, the radii are given by simple empirically based expressions involving effective atomic charges of the solute atoms that fit the solute molecular electrostatic potential and a bond length-dependent factor to account for atomic size and hybridization. The scheme shows substantial qualitative differences from other previously proposed schemes, for example, by assigning a large radius to the central atom of the oxoanions. This difference is put on a firm theoretical basis in the case of NO3 - through an analysis of the molecular electrostatic potential of the nitrate ion and an analysis of its interaction with a "solvent" water molecule. Despite a large positive partial charge assigned to nitrogen in the nitrate ion, the water solvent molecule continues to act as an H-bond donor in the region of the central N atom as a result of the electrostatic potential of the anion, although the water-nitrate interaction in that region is weaker than near the terminal O atoms. From these results, we surmise that the solvent molecules remain further away from the nitrogen atom, a finding that is consistent with the large radius assigned by the new scheme for nitrogen. The same qualitative feature holds true for all of the oxoanions considered here.

Original languageEnglish
Pages (from-to)5778-5788
Number of pages11
JournalJournal of Physical Chemistry A
Volume107
Issue number30
DOIs
Publication statusPublished - Jul 31 2003

Fingerprint

Solvation
solvation
nitrates
Atoms
Nitrates
electrostatics
Electrostatics
Nitrogen
cavities
radii
atoms
solutes
Molecules
Water
water
nitrogen
molecules
Ions
nitrogen atoms
Bond length

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

Theoretical characterization of oxoanion, XOm n-, solvation. / Camaioni, Donald M.; Dupuis, Michel; Bentley, John.

In: Journal of Physical Chemistry A, Vol. 107, No. 30, 31.07.2003, p. 5778-5788.

Research output: Contribution to journalArticle

Camaioni, Donald M. ; Dupuis, Michel ; Bentley, John. / Theoretical characterization of oxoanion, XOm n-, solvation. In: Journal of Physical Chemistry A. 2003 ; Vol. 107, No. 30. pp. 5778-5788.
@article{7eaca1aa5a9f4346844f328219acbb75,
title = "Theoretical characterization of oxoanion, XOm n-, solvation",
abstract = "We describe a new cavity definition protocol that yields accurate solvation energies and electrode potentials for selected oxoanions, XOm n-, including some for which other cavity protocols do not perform well enough. In this new definition scheme with cavities made of interlocked atomic spheres, the radii are given by simple empirically based expressions involving effective atomic charges of the solute atoms that fit the solute molecular electrostatic potential and a bond length-dependent factor to account for atomic size and hybridization. The scheme shows substantial qualitative differences from other previously proposed schemes, for example, by assigning a large radius to the central atom of the oxoanions. This difference is put on a firm theoretical basis in the case of NO3 - through an analysis of the molecular electrostatic potential of the nitrate ion and an analysis of its interaction with a {"}solvent{"} water molecule. Despite a large positive partial charge assigned to nitrogen in the nitrate ion, the water solvent molecule continues to act as an H-bond donor in the region of the central N atom as a result of the electrostatic potential of the anion, although the water-nitrate interaction in that region is weaker than near the terminal O atoms. From these results, we surmise that the solvent molecules remain further away from the nitrogen atom, a finding that is consistent with the large radius assigned by the new scheme for nitrogen. The same qualitative feature holds true for all of the oxoanions considered here.",
author = "Camaioni, {Donald M.} and Michel Dupuis and John Bentley",
year = "2003",
month = "7",
day = "31",
doi = "10.1021/jp0343537",
language = "English",
volume = "107",
pages = "5778--5788",
journal = "Journal of Physical Chemistry A",
issn = "1089-5639",
publisher = "American Chemical Society",
number = "30",

}

TY - JOUR

T1 - Theoretical characterization of oxoanion, XOm n-, solvation

AU - Camaioni, Donald M.

AU - Dupuis, Michel

AU - Bentley, John

PY - 2003/7/31

Y1 - 2003/7/31

N2 - We describe a new cavity definition protocol that yields accurate solvation energies and electrode potentials for selected oxoanions, XOm n-, including some for which other cavity protocols do not perform well enough. In this new definition scheme with cavities made of interlocked atomic spheres, the radii are given by simple empirically based expressions involving effective atomic charges of the solute atoms that fit the solute molecular electrostatic potential and a bond length-dependent factor to account for atomic size and hybridization. The scheme shows substantial qualitative differences from other previously proposed schemes, for example, by assigning a large radius to the central atom of the oxoanions. This difference is put on a firm theoretical basis in the case of NO3 - through an analysis of the molecular electrostatic potential of the nitrate ion and an analysis of its interaction with a "solvent" water molecule. Despite a large positive partial charge assigned to nitrogen in the nitrate ion, the water solvent molecule continues to act as an H-bond donor in the region of the central N atom as a result of the electrostatic potential of the anion, although the water-nitrate interaction in that region is weaker than near the terminal O atoms. From these results, we surmise that the solvent molecules remain further away from the nitrogen atom, a finding that is consistent with the large radius assigned by the new scheme for nitrogen. The same qualitative feature holds true for all of the oxoanions considered here.

AB - We describe a new cavity definition protocol that yields accurate solvation energies and electrode potentials for selected oxoanions, XOm n-, including some for which other cavity protocols do not perform well enough. In this new definition scheme with cavities made of interlocked atomic spheres, the radii are given by simple empirically based expressions involving effective atomic charges of the solute atoms that fit the solute molecular electrostatic potential and a bond length-dependent factor to account for atomic size and hybridization. The scheme shows substantial qualitative differences from other previously proposed schemes, for example, by assigning a large radius to the central atom of the oxoanions. This difference is put on a firm theoretical basis in the case of NO3 - through an analysis of the molecular electrostatic potential of the nitrate ion and an analysis of its interaction with a "solvent" water molecule. Despite a large positive partial charge assigned to nitrogen in the nitrate ion, the water solvent molecule continues to act as an H-bond donor in the region of the central N atom as a result of the electrostatic potential of the anion, although the water-nitrate interaction in that region is weaker than near the terminal O atoms. From these results, we surmise that the solvent molecules remain further away from the nitrogen atom, a finding that is consistent with the large radius assigned by the new scheme for nitrogen. The same qualitative feature holds true for all of the oxoanions considered here.

UR - http://www.scopus.com/inward/record.url?scp=0042197595&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0042197595&partnerID=8YFLogxK

U2 - 10.1021/jp0343537

DO - 10.1021/jp0343537

M3 - Article

VL - 107

SP - 5778

EP - 5788

JO - Journal of Physical Chemistry A

JF - Journal of Physical Chemistry A

SN - 1089-5639

IS - 30

ER -