| Popis: |
We present a study of the ground and triplet state properties of C$\sb{60}$O. UV-vis spectroscopy and a gravimetric analysis are used to produce a quantitative electronic absorption spectrum. Spectrofluorimetry reveals that the fluorescence quantum yield of C$\sb{60}$O is $8.1\times 10\sp{-4}$, which is a factor of 2.5 higher than that of C$\sb{60}$. Transient absorption spectroscopy is used to study the triplet state of C$\sb{60}$O, which is seen to exhibit complex decay kinetics. A possible explanation for this behavior involving triplet mediated epoxide ring opening is presented. The intrinsic triplet lifetime is determined to be 6.8 $\pm$ 0.3 $\mu$s, making C$\sb{60}$O the shortest lived fullerene derivative studied to date. Additional studies reveal that the decay of C$\sb{60}$O triplets has a mild temperature dependence corresponding to an E$\sb{\rm a}$ value of 4.5 $\mu$ 0.6 kJ/mol, whilt self-quenching is seen to play a negligible role. Furthermore, solutions of C$\sb{60}$O are shown to be unstable with respect to temperature, generating unknown impurities even at room temperature. Mass spectrometric studies failed to unambiguously identify the product contaminant. |
