Electronic Coupling in Tetraanisylarylenediamine Mixed-Valence Systems: The Interplay between Bridge Energy and Geometric Factors
摘要:
We have investigated three organic mixed-valence systems that possess nearly identical inter-redox site distances and differ by the nature of the bridging units benzene, naphthalene, and anthracene: the N,N,N',N'-tetra(4-methoxyphenyl)-1,4-phenylenene-diamine radical cation (1(+)), the 1,4-bis(N,N-di(4-methoxyphenyl)-amino)naphthalene radical cation (2(+)), and the 9,10-bis(N,N-di(4-methoxyphenyl)amino)anthracene radical cation (3(+)). The electronic interactions in these systems have been studied by means of gas-phase ultraviolet photoelectron spectroscopy, vis/NIR spectroscopy, and electronic-structure calculations. The experimental and theoretical results concur to indicate that the strength of electronic interaction decreases in the following order of bridging units: benzene > naphthalene > anthracene. This finding contradicts the usual expectation that anthracene is superior to benzene as a driving force for electronic communication. We explain these results in terms of a super-exchange mechanism and its strong dependence on steric interactions.
作者:Yuanting Su、Xingyong Wang、Yuantao Li、You Song、Yunxia Sui、Xinping Wang
DOI:10.1002/anie.201410256
日期:2015.1.26
no]arene dications 12+–32+ have been synthesized and characterized. Their electronic structures were investigated by various experiments assisted by theoretical calculations. It was found that they are singlets in the ground state and that their diradical character is dependent on the bridging moiety. 32+ has a smaller singlet–triplet energy gap and its excited triplet state is thermally readily accessible
Electronic Coupling in Tetraanisylarylenediamine Mixed-Valence Systems: The Interplay between Bridge Energy and Geometric Factors
作者:Christoph Lambert、Chad Risko、Veaceslav Coropceanu、Jürgen Schelter、Stephan Amthor、Nadine E. Gruhn、Jason C. Durivage、Jean-Luc Brédas
DOI:10.1021/ja0512172
日期:2005.6.1
We have investigated three organic mixed-valence systems that possess nearly identical inter-redox site distances and differ by the nature of the bridging units benzene, naphthalene, and anthracene: the N,N,N',N'-tetra(4-methoxyphenyl)-1,4-phenylenene-diamine radical cation (1(+)), the 1,4-bis(N,N-di(4-methoxyphenyl)-amino)naphthalene radical cation (2(+)), and the 9,10-bis(N,N-di(4-methoxyphenyl)amino)anthracene radical cation (3(+)). The electronic interactions in these systems have been studied by means of gas-phase ultraviolet photoelectron spectroscopy, vis/NIR spectroscopy, and electronic-structure calculations. The experimental and theoretical results concur to indicate that the strength of electronic interaction decreases in the following order of bridging units: benzene > naphthalene > anthracene. This finding contradicts the usual expectation that anthracene is superior to benzene as a driving force for electronic communication. We explain these results in terms of a super-exchange mechanism and its strong dependence on steric interactions.