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The toluene extract of the fluffy carbon material produced by resistive heating of graphite contains a variety of molecules larger than C(60) and C(70) in a total amount of 3 to 4% by weight. Repeated chromatography of this material on neutral alumina has led to the isolation of stable solid samples of C(76), C(84), C(90), and C(94). The characterization, which includes mass spectrometry, (13)C nuclear magnetic resonance, electronic absorption (ultraviolet/visible) and vibrational (infrared) spectroscopy identifies these all-carbon molecules as higher fullerenes. In addition, C(70)O, a stable oxide, has been isolated that is structurally and electronically closely related to D5h-C(70). This compound forms during the resistive heating process and probably has an oxygen atom inserted between two carbon atoms on the convex external surface of the C(70) skeleton.

component (t = 4.7 ns). This rvalue is consistent with previous (room temperature) estimates of donor-acceptor center to center distance of 25 A. The most important result is that the simplified kinetics at room temperature argue that any structural states of the complex which arc trapped at 77 K are largely equilibrated at 300 K within 5 ns. This result suggests that motion at the cytc/ccp interface can be quite rapid and offers experimental support for the rapid restricted dimensional diffusion model of the eyie-eep complex suggested by Brownian dynamics.8 With this information now available, more detailed insight into the nature of the binding sites in principle could be obtained by comparing the decay distributions for the native systems with those for site-specific mutants.9'10 Such studies are in progress.

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