Microhydration and the enhanced acidity of free radicals

John Christopher Walton

doi:10.3390/molecules23020423

Microhydration and the enhanced acidity of free radicals

Research output: Contribution to journal › Article › peer-review

Abstract

Recent theoretical research employing a continuum solvent model predicted that radical centers would enhance the acidity (RED-shift) of certain proton-donor molecules. Microhydration studies employing a DFT method are reported here with the aim of establishing the effect of the solvent micro-structure on the acidity of radicals with and without RED-shifts. Microhydration cluster structures were obtained for carboxyl, carboxy-ethynyl, carboxy-methyl, and hydroperoxyl radicals. The numbers of water molecules needed to induce spontaneous ionization were determined. The hydration clusters formed primarily round the CO₂ units of the carboxylate-containing radicals. Only 4 or 5 water molecules were needed to induce ionization of carboxyl and carboxy-ethynyl radicals, thus corroborating their large RED-shifts.

Original language	English
Article number	423
Journal	Molecules
Volume	23
Issue number	2
DOIs	https://doi.org/10.3390/molecules23020423
Publication status	Published - 14 Feb 2018

Keywords

Free radicals
Acidity
DFT computations
Hydration

Access to Document

10.3390/molecules23020423Licence: CC BY

Walton_2018_Molecules_MicroHydFreeRad_CCBY-VoR
Copyright 2018 the author. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
Final published version, 1.21 MBLicence: CC BY

Cite this

@article{bf36221d9c694668be6f4b8f439a161a,

title = "Microhydration and the enhanced acidity of free radicals",

abstract = "Recent theoretical research employing a continuum solvent model predicted that radical centers would enhance the acidity (RED-shift) of certain proton-donor molecules. Microhydration studies employing a DFT method are reported here with the aim of establishing the effect of the solvent micro-structure on the acidity of radicals with and without RED-shifts. Microhydration cluster structures were obtained for carboxyl, carboxy-ethynyl, carboxy-methyl, and hydroperoxyl radicals. The numbers of water molecules needed to induce spontaneous ionization were determined. The hydration clusters formed primarily round the CO2 units of the carboxylate-containing radicals. Only 4 or 5 water molecules were needed to induce ionization of carboxyl and carboxy-ethynyl radicals, thus corroborating their large RED-shifts.",

keywords = "Free radicals, Acidity, DFT computations, Hydration",

author = "Walton, \{John Christopher\}",

note = "The author thanks EaStCHEM for financial support. ",

year = "2018",

month = feb,

day = "14",

doi = "10.3390/molecules23020423",

language = "English",

volume = "23",

journal = "Molecules",

issn = "1420-3049",

publisher = "Multidisciplinary Digital Publishing Institute (MDPI)",

number = "2",

}

TY - JOUR

T1 - Microhydration and the enhanced acidity of free radicals

AU - Walton, John Christopher

N1 - The author thanks EaStCHEM for financial support.

PY - 2018/2/14

Y1 - 2018/2/14

N2 - Recent theoretical research employing a continuum solvent model predicted that radical centers would enhance the acidity (RED-shift) of certain proton-donor molecules. Microhydration studies employing a DFT method are reported here with the aim of establishing the effect of the solvent micro-structure on the acidity of radicals with and without RED-shifts. Microhydration cluster structures were obtained for carboxyl, carboxy-ethynyl, carboxy-methyl, and hydroperoxyl radicals. The numbers of water molecules needed to induce spontaneous ionization were determined. The hydration clusters formed primarily round the CO2 units of the carboxylate-containing radicals. Only 4 or 5 water molecules were needed to induce ionization of carboxyl and carboxy-ethynyl radicals, thus corroborating their large RED-shifts.

AB - Recent theoretical research employing a continuum solvent model predicted that radical centers would enhance the acidity (RED-shift) of certain proton-donor molecules. Microhydration studies employing a DFT method are reported here with the aim of establishing the effect of the solvent micro-structure on the acidity of radicals with and without RED-shifts. Microhydration cluster structures were obtained for carboxyl, carboxy-ethynyl, carboxy-methyl, and hydroperoxyl radicals. The numbers of water molecules needed to induce spontaneous ionization were determined. The hydration clusters formed primarily round the CO2 units of the carboxylate-containing radicals. Only 4 or 5 water molecules were needed to induce ionization of carboxyl and carboxy-ethynyl radicals, thus corroborating their large RED-shifts.

KW - Free radicals

KW - Acidity

KW - DFT computations

KW - Hydration

UR - https://www.scopus.com/pages/publications/85042208473

U2 - 10.3390/molecules23020423

DO - 10.3390/molecules23020423

M3 - Article

SN - 1420-3049

VL - 23

JO - Molecules

JF - Molecules

IS - 2

M1 - 423

ER -

Microhydration and the enhanced acidity of free radicals

Abstract

Keywords

Access to Document

Other files and links

Fingerprint

Cite this