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Title: Dissociation of Fumaric Acid: Spectrophotometric Investigation in Aqueous Solutions from 10 to 90ºC and Theoretical Considerations"

Abstract

The dissociation constants of fumaric acid were extracted from uv-vis spectra in the 10-90°C range. These values were used to extract thermodynamic parameters that showed the temperature effects on the dissociations reactions to be dominantly driven by the solvent. The molar absorption coefficients for the fumaric acid, the bifumarate and fumarate species, can be accurately reproduced with the two-term Gauss-Lorentz equation. Deconvolution of these bands showed strong π-π* transitions for all species and weaker charge-transfer-to-solvent transitions for the charged species. TDDFT calculations were used to identify the most important molecular orbitals involved in the vertical excitations of the fumaric acid species. The electron population and their states of delocalisation were also estimated with topological analyses of the electron density and of the Becke-Edgecombe Electron Localisation Function.

Authors:
;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
876980
Report Number(s):
PNNL-SA-47075
Journal ID: ISSN 0095-9782; JSLCAG; TRN: US200608%%228
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solution Chemistry, 34(10):1167-1190; Journal Volume: 34; Journal Issue: 10
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION; AQUEOUS SOLUTIONS; DISSOCIATION; ELECTRON DENSITY; FUMARIC ACID; TEMPERATURE DEPENDENCE; THERMODYNAMICS; ULTRAVIOLET SPECTRA; VISIBLE SPECTRA

Citation Formats

Boily, Jean F., and Seward, Terry M. Dissociation of Fumaric Acid: Spectrophotometric Investigation in Aqueous Solutions from 10 to 90ºC and Theoretical Considerations". United States: N. p., 2005. Web. doi:10.1007/s10953-005-7694-9.
Boily, Jean F., & Seward, Terry M. Dissociation of Fumaric Acid: Spectrophotometric Investigation in Aqueous Solutions from 10 to 90ºC and Theoretical Considerations". United States. doi:10.1007/s10953-005-7694-9.
Boily, Jean F., and Seward, Terry M. Thu . "Dissociation of Fumaric Acid: Spectrophotometric Investigation in Aqueous Solutions from 10 to 90ºC and Theoretical Considerations"". United States. doi:10.1007/s10953-005-7694-9.
@article{osti_876980,
title = {Dissociation of Fumaric Acid: Spectrophotometric Investigation in Aqueous Solutions from 10 to 90ºC and Theoretical Considerations"},
author = {Boily, Jean F. and Seward, Terry M.},
abstractNote = {The dissociation constants of fumaric acid were extracted from uv-vis spectra in the 10-90°C range. These values were used to extract thermodynamic parameters that showed the temperature effects on the dissociations reactions to be dominantly driven by the solvent. The molar absorption coefficients for the fumaric acid, the bifumarate and fumarate species, can be accurately reproduced with the two-term Gauss-Lorentz equation. Deconvolution of these bands showed strong π-π* transitions for all species and weaker charge-transfer-to-solvent transitions for the charged species. TDDFT calculations were used to identify the most important molecular orbitals involved in the vertical excitations of the fumaric acid species. The electron population and their states of delocalisation were also estimated with topological analyses of the electron density and of the Becke-Edgecombe Electron Localisation Function.},
doi = {10.1007/s10953-005-7694-9},
journal = {Journal of Solution Chemistry, 34(10):1167-1190},
number = 10,
volume = 34,
place = {United States},
year = {Thu Nov 17 00:00:00 EST 2005},
month = {Thu Nov 17 00:00:00 EST 2005}
}
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