Octopolar Chromophores Based on Donor- and Acceptor-Substituted 1,3,5-Tris(phenylethynyl)benzenes: Impact of meta-Conjugation on the Molecular and Electronic Structure by Means of Spectroscopy and Theory was written by Moreno Oliva, Maria;Casado, Juan;Hennrich, Gunther;Lopez Navarrete, Juan T.. And the article was included in Journal of Physical Chemistry B in 2006.Application of 3268-21-1 This article mentions the following:
The mol. and electronic structures of all-meta-substituted phenylacetylene mesitylenes peripherally substituted with donor or acceptor (D-A) groups are studied. The impact of meta- and para-substitution patterns is also analyzed by employing Raman and optical spectroscopies in conjunction with theor. calculations Outer Ph rings display a partial quinoid character induced by two different motifs: (i) outer phenyls â?triple bond charge transfer for the cases where these phenyls are substituted with electron-donors; (ii) double electron withdrawing effect in the mols. with the peripheral phenyls substituted with electron acceptors. A moderate tuning of the optical gap is observed in agreement with the partial blockade of Ï-electron conjugation exerted by the meta disposition. The orbital structure of the compounds partially preserves that of the mesitylene group showing extra-conjugation due to the addition of the arms, so that conjugation is not entirely obstructed but partially impeded in the ground electronic state (i.e., electron occupied orbitals). As for the excited states, the low-lying energy empty orbitals offer better conditions for full conjugation over the whole mol. scaffold. Interesting optical properties such as overlapping centers along the lowest energy optical excitations and enhanced optical transparency with importance for the application of these materials in optoelectronics were justified from the electronic structure. A greater degree of quinoidization, and more allowed Ï-electron delocalization, over the entire mol. is recognized in the case of linear phenylacetylenes substituting in para positions the central core. In the experiment, the researchers used many compounds, for example, 1,4-Diiodo-2,3,5,6-tetramethylbenzene (cas: 3268-21-1Application of 3268-21-1).
1,4-Diiodo-2,3,5,6-tetramethylbenzene (cas: 3268-21-1) belongs to iodide derivatives. In general, organic iodides are light-sensitive and turn yellow during storage, owing to the formation of iodine. In the chemical industry, alkyl iodides serve as excellent alkylating agents and, specifically, methyl iodide is used as a methylating agent in the synthesis of various pharmaceutical drugs.Application of 3268-21-1
Referemce:
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com