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Previous high-resolution electron microscopy (HREM) observations of the carbon nanotubes have led to a "Russian doll" structural model that is based on hollow concentric cylinders capped at both ends. The structures of the carbon nanotubes and particles were characterized here by bulk physical and chemical property measurements. The individual nanostructure is as compressible as graphite in the c axis, and such nanostructures can be intercalated with potassium and rubidium, leading to a saturation composition of "MC(8)." These results are counter to expectations that are based on a Russian doll structure. HREM after intercalation with potassium and deintercalation indicates that individual nanoparticles are a "paper-mache" of smaller graphite layers. Direct current magnetization and electron spin resonance measurements indicate that the electronic properties of the nanostructures are distinctly different from those of graphite. Although the nanostructures have distinct morphologies and electronic properties, they are highly defective and have a local structure similar to turbostratic graphite.

Meissner-eA'ect and microwave-absorption measurements on bulk samples show that Rb"C60is superconducting with a maximum transition temperature of 28 K. This is a 10-K (60%) increase over the Kdoped material. Only Ba06K04Bi03 and the cuprate superconductors have higher transition temperatures.

The complex dielectric constant of isoamyl bromide has been measured at 1,3, and 9 kMc between -75° and 25°C. Complex plane plots indicate an asymmetric, skewed-arc distribution of relaxation times, with the shape of the distribution function not being appreciably temperature dependent. A defect diffusion model is proposed to explain the dielectric behavior of this system. This model implies that the relaxation of a molecule is more probable immediately after one of its neighbors has relaxed than at an arbitrary time. A distribution of relaxation times is derived which, under the appropriate conditions, closely resembles that of the empirical skewed-arc function.