In:
Photochemistry and Photobiology, Wiley, Vol. 96, No. 5 ( 2020-09), p. 1140-1143
Kurzfassung:
A unique approach is used to relate the HOMO‐LUMO energy difference to the difference between the ionization potential (IP) and electron affinity (EA) to assist in deducing not only the colors, but also chromophores in elemental nonmetals. Our analysis focuses on compounds with lone pair electrons and σ electrons, namely X 2 (X = F, Cl, Br, I), S 8 and P 4 . For the dihalogens, the [IP – EA] energies are found to be: F 2 (12.58 eV), Cl 2 (8.98 eV), Br 2 (7.90 eV), I 2 (6.78 eV). We suggest that the intera halogen X–X bond itself is the chromophore for these dihalogens, in which the light absorbed by the F 2 , Cl 2 , Br 2 , I 2 leads to longer wavelengths in the visible by a π → σ* transition. Trace impurities are a likely case of cyclic S 8 which contains amounts of selenium leading to a yellow color, where the [IP – EA] energy of S 8 is found to be 7.02 eV. Elemental P 4 with an [IP – EA] energy of 9.09 eV contains a tetrahedral and σ aromatic structure. In future work, refinement of the analysis will be required for compounds with π electrons and σ electrons, such as polycyclic aromatic hydrocarbons (PAHs).
Materialart:
Online-Ressource
ISSN:
0031-8655
,
1751-1097
Sprache:
Englisch
Verlag:
Wiley
Publikationsdatum:
2020
ZDB Id:
2048860-9
SSG:
12
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