Relaxation Dynamics of Electronically Excited C60− in o-Dichlorobenzene and Tetrahydrofuran Solution
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Helge Brands
Abstract
The ultrafast response of singly negatively charged C60 fullerene in solution has been investigated by femtosecond pump-probe absorption spectroscopy and transient anisotropy in the visible and near-infrared region. Pump excitation within the near-infrared band demonstrates that this spectral feature can be described as a vibrational progression associated with a single electronic transition. Relaxation of the first electronically excited state occurs primarily by internal conversion with a time constant of 3 ps, slightly depending on the solvents, tetrahydrofuran or o-dichlorobenzene, and also on the excitation wavelength. An excitation of the second electronically excited state around 530 nm leads to an ultrafast internal conversion to the first excited state with a pulse-limited time constant of less than 100 fs. As a minor channel, stimulated emission in the spectral regime of 1150–1300 nm was observed from the first electronically excited state both after near-infrared and visible excitation. After internal conversion to the electronic ground state, C60− dissipates its excess internal energy into the solvent on a longer timescale of 40–70 ps. The transient anisotropy associated with directly populating the first excited state reveals an ultrafast component decaying within 100 fs, which is attributed to ultrafast vibrational motions, conceivably arising from excited state pseudorotation.
© by Oldenbourg Wissenschaftsverlag, Karlsruhe, Germany
Artikel in diesem Heft
- Preface
- OH and NH Stretching Vibrational Relaxation of Liquid Ethanolamine
- Transient anisotropy in degenerate systems: A semi-classical approach
- First Cavity Ring-Down Spectroscopy HO2 Measurements in a Large Photoreactor
- Relaxation Dynamics of Electronically Excited C60− in o-Dichlorobenzene and Tetrahydrofuran Solution
- 3CH2 + O2: Kinetics and Product Channel Branching Ratios
- What Do We Know About the Iconic System CH3 + CH3 + M ↔ C2H6 + M?
- Thermochemistry and Kinetics for 2-Butanone-3yl Radical (CH3C(=O)CH•CH3) Reactions with O2
- Experimental and Modelling Study of the Unimolecular Thermal Decompostion of CHF3
- Combustion Chemistry of the Butane Isomers in Premixed Low-Pressure Flames
- Characterization of Rhodamine 6G Release in Electrospray Ionization by Means of Spatially Resolved Fluorescence Spectroscopy
- Femtosecond interferometry of molecular dynamics – the role of relative and absolute phase of two individual laser pulses
- Photodecarbonylation of Diphenylcyclopropenone – a Direct Pathway to Electronically Excited Diphenylacetylene?
- Yield of HO2 Radicals in the OH-Initiated Oxidation of SO2
- Pyrolysis of Ethyl Iodide as Hydrogen Atom Source: Kinetics and Mechanism in the Temperature Range 950–1200 K
- Reaction of OH and NO at Low Temperatures in the Presence of Water: the Role of Clusters
Artikel in diesem Heft
- Preface
- OH and NH Stretching Vibrational Relaxation of Liquid Ethanolamine
- Transient anisotropy in degenerate systems: A semi-classical approach
- First Cavity Ring-Down Spectroscopy HO2 Measurements in a Large Photoreactor
- Relaxation Dynamics of Electronically Excited C60− in o-Dichlorobenzene and Tetrahydrofuran Solution
- 3CH2 + O2: Kinetics and Product Channel Branching Ratios
- What Do We Know About the Iconic System CH3 + CH3 + M ↔ C2H6 + M?
- Thermochemistry and Kinetics for 2-Butanone-3yl Radical (CH3C(=O)CH•CH3) Reactions with O2
- Experimental and Modelling Study of the Unimolecular Thermal Decompostion of CHF3
- Combustion Chemistry of the Butane Isomers in Premixed Low-Pressure Flames
- Characterization of Rhodamine 6G Release in Electrospray Ionization by Means of Spatially Resolved Fluorescence Spectroscopy
- Femtosecond interferometry of molecular dynamics – the role of relative and absolute phase of two individual laser pulses
- Photodecarbonylation of Diphenylcyclopropenone – a Direct Pathway to Electronically Excited Diphenylacetylene?
- Yield of HO2 Radicals in the OH-Initiated Oxidation of SO2
- Pyrolysis of Ethyl Iodide as Hydrogen Atom Source: Kinetics and Mechanism in the Temperature Range 950–1200 K
- Reaction of OH and NO at Low Temperatures in the Presence of Water: the Role of Clusters
