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Updated: Feb 18, 2026
10:51
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
12.8K
Trapping intermediate MLCT states in low-symmetry {Ru(bpy)} complexes.
Alejandro Cadranel1, Paola S Oviedo2, German E Pieslinger2
1Department of Chemistry and Pharmacy , Interdisciplinary Center for Molecular Materials (ICMM) , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstr. 3 , 91058 Erlangen , Germany . Email: ale.cadranel@fau.de ;
Chemical Science
|November 23, 2017
Summary
Investigating ruthenium complexes [Ru(tpm)(bpy)(NCS)]+ (RubNCS) and [Ru(tpm)(bpy)(CN)]+ (RubCN), this study reveals distinct excited state dynamics. Different photoexcitation wavelengths lead to unique intermediate states and conversion pathways, impacting their photophysical properties.
Area of Science:
- Photochemistry
- Coordination Chemistry
- Physical Chemistry
Background:
- Ruthenium polypyridyl complexes are crucial in photochemistry.
- Understanding excited state dynamics is key to designing new functional materials.
- Excited state pathways influence photochemical reactivity and energy transfer.
Purpose of the Study:
- To elucidate the picosecond excited state dynamics of RubNCS and RubCN complexes.
- To compare the influence of different photoexcitation wavelengths on excited state evolution.
- To characterize intermediate excited states and their conversion to emissive states.
Main Methods:
- Transient absorption spectroscopy
- Spectroelectrochemistry
- Picosecond time-resolved measurements
Main Results:
- Both complexes exhibit emissive 3MLCT states regardless of excitation wavelength.
- 505 nm photoexcitation populates a distinct intermediate 3MLCT state with a different electronic configuration.
- This intermediate state conversion to the emissive state is kinetically hindered and observed on a 300 ps timescale.
Conclusions:
- The electronic configuration of excited states significantly impacts their spectral signatures.
- A kinetic barrier exists for the reconfiguration of intermediate excited states to emissive states.
- Excited state dynamics are sensitive to photoexcitation wavelength, influencing reaction pathways in ruthenium complexes.
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