Coexistence of ligand localized and MLCT excited states in a 2-(2{sup {prime}}-Pyridyl)benzo[g]quinoline complex of ruthenium(II)

doi:https://doi.org/10.1021/ic9412973

Title: Coexistence of ligand localized and MLCT excited states in a 2-(2{sup {prime}}-Pyridyl)benzo[g]quinoline complex of ruthenium(II)

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Abstract

The photophysical behavior of complexes of the type [(bpy){sub 2}Ru(L)](PF{sub 6}){sub 2}, where L is a 2-(2{sup {prime}}-pyridyl) quinoline or 2-(2{sup {prime}}-pyridyl)benzo[g]quinoline derivative, was investigated in acetonitrile solutions and ethanol-methanol glasses. The luminescence from each complex originates from a metal-to-ligand charge transfer excited state and the energy of the emission maxima correlate with other reported quinoline complexes of Ru(II). The 2-(2{sup {prime}}-pyridyl)-benzo[g]quinoline complex has a unique transient absorption spectrum with a decay rate constant approximately 30 times less than the luminescence decay rate constant, indicating the existence of two nonequilibrated excited states in the complex. Comparison with other related complexes suggests the long-lived transient absorption may be due to a ligand localized ({pi}{r_arrow}{pi}{sup *}) excited state. The pyridylquinoline complex exhibits behavior characteristic of a single MLCT excited state.

Authors:

Taffarel, E; Chirayil, S; Kim, W Y; Thummel, R P; Schmehl, R H ^[1]

Tulane Univ., New Orleans, LA (United States)

Publication Date:: 1996-03-27

OSTI Identifier:: 263756

DOE Contract Number:: FG05-92ER14309

Resource Type:: Journal Article

Journal Name:: Inorganic Chemistry

Additional Journal Information:: Journal Volume: 35; Journal Issue: 7; Other Information: PBD: 27 Mar 1996

Country of Publication:: United States

Language:: English

Subject:: 40 CHEMISTRY; RUTHENIUM COMPLEXES; EXCITED STATES; PHOTOCHEMISTRY; LUMINESCENCE; ABSORPTION SPECTROSCOPY; KINETICS

Citation Formats


                    Taffarel, E, Chirayil, S, Kim, W Y, Thummel, R P, Schmehl, R H, and Univ. of Houston, TX. Coexistence of ligand localized and MLCT excited states in a 2-(2{sup {prime}}-Pyridyl)benzo[g]quinoline complex of ruthenium(II).  United States: N. p., 1996. 
        Web.  doi:10.1021/ic9412973.

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                    Taffarel, E, Chirayil, S, Kim, W Y, Thummel, R P, Schmehl, R H, & Univ. of Houston, TX. Coexistence of ligand localized and MLCT excited states in a 2-(2{sup {prime}}-Pyridyl)benzo[g]quinoline complex of ruthenium(II).  United States.  https://doi.org/10.1021/ic9412973

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                    Taffarel, E, Chirayil, S, Kim, W Y, Thummel, R P, Schmehl, R H, and Univ. of Houston, TX. Wed .  
        "Coexistence of ligand localized and MLCT excited states in a 2-(2{sup {prime}}-Pyridyl)benzo[g]quinoline complex of ruthenium(II)".  United States.  https://doi.org/10.1021/ic9412973.

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@article{osti_263756,

  title        = {Coexistence of ligand localized and MLCT excited states in a 2-(2{sup {prime}}-Pyridyl)benzo[g]quinoline complex of ruthenium(II)},

  author       = {Taffarel, E and Chirayil, S and Kim, W Y and Thummel, R P and Schmehl, R H and Univ. of Houston, TX},

  abstractNote = {The photophysical behavior of complexes of the type [(bpy){sub 2}Ru(L)](PF{sub 6}){sub 2}, where L is a 2-(2{sup {prime}}-pyridyl) quinoline or 2-(2{sup {prime}}-pyridyl)benzo[g]quinoline derivative, was investigated in acetonitrile solutions and ethanol-methanol glasses. The luminescence from each complex originates from a metal-to-ligand charge transfer excited state and the energy of the emission maxima correlate with other reported quinoline complexes of Ru(II). The 2-(2{sup {prime}}-pyridyl)-benzo[g]quinoline complex has a unique transient absorption spectrum with a decay rate constant approximately 30 times less than the luminescence decay rate constant, indicating the existence of two nonequilibrated excited states in the complex. Comparison with other related complexes suggests the long-lived transient absorption may be due to a ligand localized ({pi}{r_arrow}{pi}{sup *}) excited state. The pyridylquinoline complex exhibits behavior characteristic of a single MLCT excited state.},

  doi          = {10.1021/ic9412973},

  url          = {https://www.osti.gov/biblio/263756},
  journal      = {Inorganic Chemistry},
number       = 7,

  volume       = 35,

  place        = {United States},

  year         = {1996},

  month        = {3}

}

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https://doi.org/10.1021/ic9412973

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