No abstract

The picotube molecule is a highly symmetric hydrocarbon, closely related to a very short ͑4,4͒ carbon nanotube. We present a thorough experimental and theoretical study of the physical properties of picotube crystals. In x-ray diffraction experiments we find the picotube molecules to display D 2d symmetry. We identify the most intense Raman peaks as A 1 modes with polarization-dependent Raman measurements. Ab initio calculations of the structural, electronic, and vibrational properties of picotubes are in excellent agreement with our experiments. We assign the measured vibrations to displacement eigenvectors including those analogous to the nanotube high-energy mode, the D mode, and the radial-breathing mode.

ARTICLEenergy, 44 the high absorption of visible light of our samples indicates their potential in the field of solar energy.

Local structures around Fe and chemical shifts in X -ray absorption fine structure (XAFS) spectra were investigated for synthetic /Fetotal ratio in the system by the XAFS method would appear to be less than ±0.10, and higher reliability than this value would be acquired in the comparison of relative values at half -maximum positions.

The crystal structure of