Thermodynamic of solvation, solute - Solvent electron transfer and ionization potential of BSCAPE molecule and its UV-vis spectra in aqueous solution

Olivier Holtomo; Mama Nsangou; Jean Jules Fifen; Ousmanou Motapon

doi:10.1016/j.jmgm.2019.06.016

Thermodynamic of solvation, solute - Solvent electron transfer and ionization potential of BSCAPE molecule and its UV-vis spectra in aqueous solution

J Mol Graph Model. 2019 Nov:92:100-111. doi: 10.1016/j.jmgm.2019.06.016. Epub 2019 Jun 28.

Authors

Olivier Holtomo¹, Mama Nsangou², Jean Jules Fifen³, Ousmanou Motapon⁴

Affiliations

¹ Department of Physics, Faculty of Science, University of Bamenda, Bambili, P. O. Box 39, Cameroon; Laboratory of Fundamental Physics, Faculty of Science, University of Douala, Douala, P. O. Box 24157, Cameroon. Electronic address: holtomoo@gmail.com.
² Department of Physics, Higher Teacher's Training College, University of Maroua, Maroua, P. O. Box 46, Cameroon; Department of Physics, Faculty of Science, University of Ngaoundere, Ngaoundere, P. O. Box 454, Cameroon.
³ Department of Physics, Faculty of Science, University of Ngaoundere, Ngaoundere, P. O. Box 454, Cameroon.
⁴ Laboratory of Fundamental Physics, Faculty of Science, University of Douala, Douala, P. O. Box 24157, Cameroon; Department of Physics, Faculty of Science, University of Maroua, Maroua, P. O. Box 814, Cameroon.

PMID: 31349123
DOI: 10.1016/j.jmgm.2019.06.016

Abstract

The molecular system 2-Phenylethyl (2E)-3-(1-benzenesulfonyl-4,5-dihydroxyphenyl) acrylate (BSCAPE) is a phenolic acid that covers a large spectrum of biological properties. The investigations of solvation and oxidation processes of BSCAPE molecule by computational means were the challenge of this present work. Water was required for solvation throughout the work. The explicit H₂O were sequentially added to form the complexes BSCAPE(H₂O)_n=0-11. The discrete - continuum model was at the heart of this work. DFT and TD-DFT both associated to the continuum model SMD were required. Hence, the structures, the solvation energies, the energies of solute - solvent electron transfer (SSET), the ionisation potential (IP), and the UV-vis spectra were studied. It comes out that, the structure of the CAPE part included in BSCAPE agrees well with the available experimental values of CAPE but with a minor influence due to the presence of benzensulfonyl group. The enthalpy and free energy of solvation increase linearly with nH₂O. The global reactivity indexes were assessed to appreciate the oxidation of BSCAPE. The latter quality was strongly assessed by the enthalpy and free energy of SSET and IP. The SSET potential increase with nH₂O and the size of water clusters. The values 723.16 and 711.62 kJ/mol were found for enthalpy and free energy of IP respectively. Then in aqueous solution, the results fall down and upon addition of nH₂O, they approach gas phase value for 11H₂O and still are not stabilized. Therefore, the resistance to oxidation starts to raise at this level. Elsewhere, the UV-vis spectra of BSCAPE present four important peaks about 279.3, 234.8, 208.4 and 199.4 nm in gaseous state. The excitation shifts to the red as the number of H₂O increase. Their oscillator strengths also increase with solvation.

Keywords: DFT; Discrete-continuum; IP; SSET; Solvation; Structure of BSCAPE; UV–vis.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Algorithms
Caffeic Acids / chemistry*
Density Functional Theory
Electron Transport*
Ions / chemistry*
Models, Chemical*
Models, Molecular
Phenylethyl Alcohol / analogs & derivatives*
Phenylethyl Alcohol / chemistry
Photoelectron Spectroscopy*
Solutions
Solvents / chemistry*
Thermodynamics*

Substances

Caffeic Acids
Ions
Solutions
Solvents
caffeic acid phenethyl ester
Phenylethyl Alcohol