The conduction electron spin resonance of potassium-doped graphite (KCx) was carried out. The g value of KC200 was determined to be 2.0060 at room temperature, which was the same as that of host graphite. On the other hand, the g values of KCx samples (96·≥x·≥8) were determined to be around 2.002. The X-ray diffraction measurement of KC200 showed that no clear stage structure was realized in contrast to those of the other KCx samples.

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We introduce some calculation methods for structure and electronic structure of various carbon materials. Some experimental spectra of Raman spectroscopy, infrared absorption, STS and STM can be directly compared with the calculated results.

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This paper elaborates on an electrochemical measurement system using personal computer for development of carbon anode materials for Li ion secondary battery. Some analysis methods for the obtained data by the system are explained. Theoretical investigations on the electrochemical properties of carbon nanotubes are also reviewed.

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X-ray dill faction technique, have widely been ftpplicd for crystal structure charactcniation of carbon materi-als and ga c useful information. Progresses, in computer. were remarkable. which made the measurement cI diffrac-tion intensities and their correction, on di fferent factors easier. It was pointed out, therefore, that the procedures for X-ray diffraction measurements, e to he revised so as to take into account of these progresses in computation. In the present paper, computer analysts of digital data of X-ray diffraction, for instance, determination of lattice constants and crystallite size of carbon materials (Gakushin method) using profile fitting technique and calculation of integral inten-sity in the case of estimation of graphititation degree P1 was reviewed. The measurement conditions to obtain a good digital diffraction data, the procedures of smoothing and intensity correction of diffraction profile were introduced.

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Single-wall carbon nalimithes (SWNTs) htve unique structures with diameters of nanometer scales and length of mieromemrs or longer. Their properties are interesting, for example. high tensile strength and electrical properties of both semiconductors and metals depending on their structural symmetries. However. their production methods have not been well established. In this review, the methods of formation. purdication. and purity estimation of SWNTs are introduced. We also introduce single-wall carbon nanohorns (SWNH) that have SWNT-like structures and usually torm spherical aggregates with diameters fo 80-100nm. Two types of SWND aggregates are known, dahlia and bud types. They are produced by CO₂ laser ablation at room temperature. Dahlia and bud types of SWNH aggregates are produced with purities of 90%, and 70%, respectively. Among SWNH properties, gas adsorption phenomena are interesting. For example. specific surface area increases from about 300m²/g to 1000m²/g by Heating in oxygen gas at 420°C.

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