Excited‐State Intramolecular Charge‐Transfer Dynamics in 4‐Dimethylamino‐4′‐cyanodiphenylacetylene: An Ultrafast Raman Loss Spectroscopic Perspective

Please always quote using this URN: urn:nbn:de:bvb:20-opus-312280
  • Photo‐initiated intramolecular charge transfer (ICT) processes play a pivotal role in the excited state reaction dynamics in donor‐bridge‐acceptor systems. The efficacy of such a process can be improved by modifying the extent of π‐conjugation, relative orientation/twists of the donor/acceptor entities and polarity of the environment. Herein, 4‐dimethylamino‐4′‐cyanodiphenylacetylene (DACN‐DPA), a typical donor‐π‐bridge‐acceptor system, was chosen to unravel the role of various internal coordinates that govern the extent of photo‐initiated ICTPhoto‐initiated intramolecular charge transfer (ICT) processes play a pivotal role in the excited state reaction dynamics in donor‐bridge‐acceptor systems. The efficacy of such a process can be improved by modifying the extent of π‐conjugation, relative orientation/twists of the donor/acceptor entities and polarity of the environment. Herein, 4‐dimethylamino‐4′‐cyanodiphenylacetylene (DACN‐DPA), a typical donor‐π‐bridge‐acceptor system, was chosen to unravel the role of various internal coordinates that govern the extent of photo‐initiated ICT dynamics. Transient absorption (TA) spectra of DACN‐DPA in n‐hexane exhibit a lifetime of >2 ns indicating the formation of a triplet state while, in acetonitrile, a short time‐constant of ∼2 ps indicates the formation of charge transferred species. Ultrafast Raman loss spectroscopy (URLS) measurements show distinct temporal and spectral dynamics of Raman bands associated with C≡C and C=C stretching vibrations. The appearance of a new band at ∼1492 cm\(^{−1}\) in acetonitrile clearly indicates structural modification during the ultrafast ICT process. Furthermore, these observations are supported by TD‐DFT computations.show moreshow less

Download full text files

Export metadata

Additional Services

Share in Twitter Search Google Scholar Statistics
Metadaten
Author: Arvind Barak, Nishant Dhiman, Floriane Sturm, Florian Rauch, Yapamanu Adithya Lakshmanna, Karen S. Findlay, Andrew Beeby, Todd B. Marder, Siva Umapathy
URN:urn:nbn:de:bvb:20-opus-312280
Document Type:Journal article
Faculties:Fakultät für Chemie und Pharmazie / Institut für Anorganische Chemie
Language:English
Parent Title (English):ChemPhotoChem
Year of Completion:2022
Volume:6
Issue:12
Article Number:e202200146
Source:ChemPhotoChem 2022, 6(12):e202200146. DOI: 10.1002/cptc.202200146
DOI:https://doi.org/10.1002/cptc.202200146
Dewey Decimal Classification:5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften
Tag:4-dimethylamino-4′-cyanodiphenylacetylene; TD-DFT; charge transfer; transient absorption; ultrafast Raman loss spectroscopy
Release Date:2023/06/21
Licence (German):License LogoCC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International