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Excited-State Decay Paths in Tetraphenylethene Derivatives
[Image: see text] The photophysical properties of tetraphenylethene (TPE) compounds may differ widely depending on the substitution pattern, for example, with regard to the fluorescence quantum yield ϕ(f) and the propensity to exhibit aggregation-induced emission (AIE). We report combined electronic...
Autores principales: | , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Chemical
Society
2017
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5385518/ https://www.ncbi.nlm.nih.gov/pubmed/28318255 http://dx.doi.org/10.1021/acs.jpca.7b00197 |
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author | Gao, Yuan-Jun Chang, Xue-Ping Liu, Xiang-Yang Li, Quan-Song Cui, Ganglong Thiel, Walter |
author_facet | Gao, Yuan-Jun Chang, Xue-Ping Liu, Xiang-Yang Li, Quan-Song Cui, Ganglong Thiel, Walter |
author_sort | Gao, Yuan-Jun |
collection | PubMed |
description | [Image: see text] The photophysical properties of tetraphenylethene (TPE) compounds may differ widely depending on the substitution pattern, for example, with regard to the fluorescence quantum yield ϕ(f) and the propensity to exhibit aggregation-induced emission (AIE). We report combined electronic structure calculations and nonadiabatic dynamics simulations to study the excited-state decay mechanisms of two TPE derivatives with four methyl substituents, either in the meta position (TPE-4mM, ϕ(f) = 0.1%) or in the ortho position (TPE-4oM, ϕ(f) = 64.3%). In both cases, two excited-state decay pathways may be relevant, namely, photoisomerization around the central ethylenic double bond and photocyclization involving two adjacent phenyl rings. In TPE-4mM, the barrierless S(1) cyclization is favored; it is responsible for the ultralow fluorescence quantum yield observed experimentally. In TPE-4oM, both the S(1) photocyclization and photoisomerization paths are blocked by non-negligible barriers, and fluorescence is thus feasible. Nonadiabatic dynamics simulations with more than 1000 surface hopping trajectories show ultrafast cyclization upon photoexcitation of TPE-4mM, whereas TPE-4oM remains unreactive during the 1 ps simulations. We discuss the chances for spectroscopic detection of the postulated cyclic photoproduct of TPE-4mM and the relevance of our findings for the AIE process. |
format | Online Article Text |
id | pubmed-5385518 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2017 |
publisher | American Chemical
Society |
record_format | MEDLINE/PubMed |
spelling | pubmed-53855182017-04-11 Excited-State Decay Paths in Tetraphenylethene Derivatives Gao, Yuan-Jun Chang, Xue-Ping Liu, Xiang-Yang Li, Quan-Song Cui, Ganglong Thiel, Walter J Phys Chem A [Image: see text] The photophysical properties of tetraphenylethene (TPE) compounds may differ widely depending on the substitution pattern, for example, with regard to the fluorescence quantum yield ϕ(f) and the propensity to exhibit aggregation-induced emission (AIE). We report combined electronic structure calculations and nonadiabatic dynamics simulations to study the excited-state decay mechanisms of two TPE derivatives with four methyl substituents, either in the meta position (TPE-4mM, ϕ(f) = 0.1%) or in the ortho position (TPE-4oM, ϕ(f) = 64.3%). In both cases, two excited-state decay pathways may be relevant, namely, photoisomerization around the central ethylenic double bond and photocyclization involving two adjacent phenyl rings. In TPE-4mM, the barrierless S(1) cyclization is favored; it is responsible for the ultralow fluorescence quantum yield observed experimentally. In TPE-4oM, both the S(1) photocyclization and photoisomerization paths are blocked by non-negligible barriers, and fluorescence is thus feasible. Nonadiabatic dynamics simulations with more than 1000 surface hopping trajectories show ultrafast cyclization upon photoexcitation of TPE-4mM, whereas TPE-4oM remains unreactive during the 1 ps simulations. We discuss the chances for spectroscopic detection of the postulated cyclic photoproduct of TPE-4mM and the relevance of our findings for the AIE process. American Chemical Society 2017-03-20 2017-04-06 /pmc/articles/PMC5385518/ /pubmed/28318255 http://dx.doi.org/10.1021/acs.jpca.7b00197 Text en Copyright © 2017 American Chemical Society This is an open access article published under an ACS AuthorChoice License (http://pubs.acs.org/page/policy/authorchoice_termsofuse.html) , which permits copying and redistribution of the article or any adaptations for non-commercial purposes. |
spellingShingle | Gao, Yuan-Jun Chang, Xue-Ping Liu, Xiang-Yang Li, Quan-Song Cui, Ganglong Thiel, Walter Excited-State Decay Paths in Tetraphenylethene Derivatives |
title | Excited-State Decay Paths in Tetraphenylethene Derivatives |
title_full | Excited-State Decay Paths in Tetraphenylethene Derivatives |
title_fullStr | Excited-State Decay Paths in Tetraphenylethene Derivatives |
title_full_unstemmed | Excited-State Decay Paths in Tetraphenylethene Derivatives |
title_short | Excited-State Decay Paths in Tetraphenylethene Derivatives |
title_sort | excited-state decay paths in tetraphenylethene derivatives |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5385518/ https://www.ncbi.nlm.nih.gov/pubmed/28318255 http://dx.doi.org/10.1021/acs.jpca.7b00197 |
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