III-A-4 Oscillatory Fluorescence Decay of Electron-Donor-Acceptor Complex

Igor V. RUBSTOV (IMS and JAIST) and Keitaro YOSHIHARA (IMS and JAIST)

[J. Phys. Chem. 101, 6138 (1997)]

We observed an oscillatory fluorescence decay dynamics of electron-donor-acceptor complex of hexamethylbenzene and tetracyanoethylene in CCl4 at room temperature. A fast spontaneous fluorescence decay with a characteristic time of 105 ± 20 fs was measured (Figure 1). An under-damped oscillation of fluorescence is overlapped with this fast decay. The period of the oscillation is 209 ± 4 fs which corresponds to a frequency of 159 ± 3 cm-1. The oscillation is tentatively assigned to an intermolecular vibration in the excited state. The damping time of the oscillations is 280 ± 30 fs.

Figure 1. Fluorescence decay observed at 777 nm. The best fit which includes sinusoidal part is shown. The oscillatory part is also shown separately.


back to CONTENTS of Research Activities III