The Hammett correlation between distyrylbenzene substituents and chemiluminescence efficiency providing various ρ-values for peroxyoxalate chemiluminescence of several oxalates
| Autor: | Susumu Narita, Takayuki Maruyama, Jiro Motoyoshiya |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Peroxyoxalate chemiluminescence
General Chemical Engineering Substituent Ab initio General Physics and Astronomy Frontier molecular orbital theory General Chemistry Photochemistry Peroxyoxalate law.invention chemistry.chemical_compound chemistry law Physical chemistry Molecular orbital Singlet state HOMO/LUMO Hammett correlation High-energy intermediate Chemiluminescence |
| Zdroj: | Journal of Photochemistry and Photobiology A: Chemistry. 252:222-231 |
| ISSN: | 1010-6030 |
| DOI: | 10.1016/j.jphotochem.2012.12.006 |
| Popis: | Peroxyoxalate chemiluminescence (PO-CL) was investigated using eight oxalates with various phenol moieties and the distyrylbenzene (DSB) fluorophores with various substituents. The ρ-values in the Hammett correlation between the substituent constants (σp+) of the DSBs and the singlet chemiexcitation yields (ΦS) for the PO-CL reactions varied from −0.50 to −1.01 depending on the oxalate structure, and the reactive oxalates tended to afford the higher absolute ρ-values but with a few exceptions. Based on the CIEEL mechanism, these experimental observations suggest that the aryloxy groups still remain in the 1,2-dioxetanones (DOTs), which are the postulated high-energy intermediates, and control the electronic properties of DOTs as electron-acceptors. The LUMO energies of the DOTs calculated by the ab initio method with a B3LYP/6-31g(d) basis set reveal that the lower the DOT-LUMO energies, the higher the absolute ρ-values were provided for the corresponding oxalates, as predicted by the frontier molecular orbital (FMO) theory. Thus, the chemical species interacting with the DSBs would be not unitary and will be DOTs. Article Journal of Photochemistry and Photobiology A: Chemistry. 252:222-231 (2013) |
| Databáze: | OpenAIRE |
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