Calculation of relative nonradiative decay rate constants from emission spectral profiles. Polypyridyl complexes of Ru(II)

Journal Article · Thu Jan 10 04:00:00 EST 1991 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100154a013· OSTI ID:5974476

Barqawi, K R; Murtaza, Z; Meyer, T J ^[1]

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1. Univ. of North Carolina, Chapel Hill (USA)

Low temperature emission spectra, lifetimes, and emission quantum yields have been acquired at 157 K in 4:1 (v:v) ethanol-methanol for a series of polypyridyl complexes of Ru{sup II}. At this low temperature, excited state behavior is free of complications arising from dd or higher lying MLCT states. Emission spectral profiles have been fit by using a model that includes contributions from an averaged medium frequency ring stretching mode, a low frequency mode, and the solvent. Linear correlations exist between: (1) the electron-vibrational coupling constant for the medium frequency mode and the energy gap between the excited and ground states (E{sub 0}), (2) In (k{sub nr} {times} 1s) and E{sub 0} where k{sub nr} is the nonradiative decay rate constant, (3) In (k{sub nr} {times} 1s) and vibrational overlap factors for nonradiative decay, calculated by using the parameters obtained by emission spectral fitting. Compared to earlier correlations at room temperature, the quality of the energy gap law correlations is greatly improved. This illustrates the importance of making equivalent state to state comparisons when discussing the excited state properties of these complexes.

• OSTI ID: 5974476
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 95:1; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102* -- Chemical & Spectral Procedures
COMPLEXES
COUPLING CONSTANTS
DATA
EMISSION SPECTRA
ENERGY LEVELS
EXCITED STATES
EXPERIMENTAL DATA
INFORMATION
LOW TEMPERATURE
MEASURING METHODS
NUMERICAL DATA
PYRIDYL RADICALS
RADICALS
RUTHENIUM COMPLEXES
SPECTRA
TRANSITION ELEMENT COMPLEXES