Production and purification of iCeC 82Ce-containing endohedral fullerenes were produced by the so-called reversed arc technique developed by the Nagoya group as described previously. 1 A Ce-doped graphite rod (anode) was kept a few mm apart from a graphite block (cathode) in a vacuum chamber. The rod and the block were connected to an external power supply and high current was passed through them (300 -500 A). The vaporisation took place in He atmosphere (50 -100 Torr). The resulting soot contained 10 -20 % fullerenes.The fullerenes were soxhlet-extracted from the soot for ca. 4 hours in o-xylene. A twostage high performance liquid chromatography (HPLC) method was employed to isolate individual fullerene isomers. In the first stage, the o-xylene solution was passed through a Cosmosil 5PBB column (20 250 mm, Nacalai Tesque) with o-xylene eluent (flow rate: 11 ml/min). Figure 1 shows the HPLC chromatogram of Ce-containing endohedral fullerenes.

We report the purification of the nitrogen-containing incar-fullerenes iNC(60) and iNC(70), and their characterisation by UV-Vis absorption spectroscopy.

Most experts agree that it is too early to say how quantum computers will eventually be built, and several nanoscale solid-state schemes are being implemented in a range of materials. Nanofabricated quantum dots can be made in designer configurations, with established technology for controlling interactions and for reading out results. Epitaxial quantum dots can be grown in vertical arrays in semiconductors, and ultrafast optical techniques are available for controlling and measuring their excitations. Single-walled carbon nanotubes can be used for molecular self-assembly of endohedral fullerenes, which can embody quantum information in the electron spin. The challenges of individual addressing in such tiny structures could rapidly become intractable with increasing numbers of qubits, but these schemes are amenable to global addressing methods for computation.

Single-walled carbon nanotubes (SWNTs) have been produced in high yield by the dc arc discharge technique under gravity-free conditions. Gravity-free conditions can reduce the convection flow of the buffer gas during the arc discharge, which results in the increase of high thermostatic volume around the arc flame. The yields of both the total soot and SWNTs in soot are significantly increased. Raman spectroscopy and transmission electron microscopy analyses reveal that the diameter distribution of SWNTs has shifted to a larger diameter region under the gravity-free condition. The annealing process in high-thermostatic atmosphere is a crucial experimental factor to selectively synthesize a certain diameter SWNT in high yield.

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The interaction of Ce@ C 82 with clean and silver-terminated Si͑111͒ surfaces has been studied with synchrotron-radiation photoemission spectroscopy and near-edge x-ray absorption fine-structure ͑NEXAFS͒ spectroscopy. Use of an Ag/ Si͑111͒-͑ ͱ 3 ϫ ͱ 3͒R30°surface as an initial substrate enables the moleculesubstrate interaction to be progressively strengthened through controlled annealing. Although strong covalent bonding and distortion of the fullerene cage are observed following the removal of the Ag-induced reconstruction ͑above 550°C͒, the cerium atom's valence and overall electronic structure, as probed by Ce 3d NEXAFS, appear to be remarkably unaffected.

Synchrotron-based photoelectron spectroscopy (PES) has been used to investigate the interaction of atomic gold and silver with a covalently bound C60-monolayer adsorbed on Si(111)7×7. In contrast to the relatively benign interaction of silver with the C60/Si(111)7×7 surface, core-level photoemission data reveal a strong interaction of gold with the underlying silicon despite the presence of a chemisorbed fullerene monolayer. The Si 2p PES data exhibit dramatic changes consistent with the formation of a gold silicide, which is also evident from the corresponding Au 4f spectra. Valence band photoemission also reveals the absence of any density of states at the Fermi level following the adsorption of either metal, indicating a negligible transfer of electrons from the adsorbed metal to the C60 cage.

Production and purification of iCeC 82Ce-containing endohedral fullerenes were produced by the so-called reversed arc technique developed by the Nagoya group as described previously. 1 A Ce-doped graphite rod (anode) was kept a few mm apart from a graphite block (cathode) in a vacuum chamber. The rod and the block were connected to an external power supply and high current was passed through them (300 -500 A). The vaporisation took place in He atmosphere (50 -100 Torr). The resulting soot contained 10 -20 % fullerenes.The fullerenes were soxhlet-extracted from the soot for ca. 4 hours in o-xylene. A twostage high performance liquid chromatography (HPLC) method was employed to isolate individual fullerene isomers. In the first stage, the o-xylene solution was passed through a Cosmosil 5PBB column (20 250 mm, Nacalai Tesque) with o-xylene eluent (flow rate: 11 ml/min). Figure 1 shows the HPLC chromatogram of Ce-containing endohedral fullerenes.