FLUORESCENCE-SPECTRA AND QUANTUM YIELDS OF BUCKMINSTERFULLERENE (C-60) IN ROOM-TEMPERATURE SOLUTIONS - NO EXCITATION WAVELENGTH DEPENDENCE

Noise-eliminated fluorescence and fluorescence excitation spectra of C60 in room-temperature hexane and toluene solutions are obtained with the application of principal component analysis. Fluorescence quantum yields of 2.0 X 10(-4) and 2.2 x 10(-4) are determined for C60 in hexane and toluene, respectively. Fluorescence spectra and fluorescence quantum yields are excitation wavelength independent for different bands of the absorption spectrum, indicating no competing decay pathways to the rapid internal conversion relaxation of the upper excited singlet states. The excited- state properties of C60 are discussed on the basis of these results, and a comparison is made between experimental and calculated fluorescence radiative rate constants.