Making Nitronaphthalene FluoresceShow others and affiliations
2021 (English)In: The Journal of Physical Chemistry Letters, E-ISSN 1948-7185, Vol. 12, no 42, p. 10295-10303Article in journal (Refereed) Published
Abstract [en]
Nitroaromatic compounds are inherently nonfluorescent, and the subpico-second lifetimes of the singlet excited states of many small nitrated polycyclic aromatic hydrocarbons, such as nitronaphthalenes, render them unfeasible for photosensitizers and photo-oxidants, despite their immensely beneficial reduction potentials. This article reports up to a 7000-fold increase in the singlet-excited-state lifetime of 1-nitronaphthalene upon attaching an amine or an N-amide to the ring lacking the nitro group. Varying the charge-transfer (CT) character of the excited states and the medium polarity balances the decay rates along the radiative and the two nonradiative pathways and can make these nitronaphthalene derivatives fluoresce. The strong electron-donating amine suppresses intersystem crossing (ISC) but accommodates CT pathways of nonradiate deactivation. Conversely, the N-amide does not induce a pronounced CT character but slows down ISC enough to achieve relatively long lifetimes of the singlet excited state. These paradigms are key for the pursuit of electron-deficient (n-type) organic conjugates with promising optical characteristics.
Place, publisher, year, edition, pages
AMER CHEMICAL SOC , 2021. Vol. 12, no 42, p. 10295-10303
National Category
Atom and Molecular Physics and Optics
Identifiers
URN: urn:nbn:se:liu:diva-181203DOI: 10.1021/acs.jpclett.1c02155ISI: 000713423000007PubMedID: 34653339OAI: oai:DiVA.org:liu-181203DiVA, id: diva2:1613723
Note
Funding Agencies|USA National Science FoundationNational Science Foundation (NSF) [CHE 1800602]; USA National Science Foundation (AGEP supplement fellowship); American Chemical Society Petroleum Research FundAmerican Chemical Society [60651ND4]; USA National Institutes of Health, National Eye Institute [R01 EY027440]; Swedish Research CouncilSwedish Research CouncilEuropean Commission [2018-05973, 2020-04600, SNIC 2020-3-29]
2021-11-232021-11-232024-07-04