Adsorption properties of copper ion-exchanged mordenite (CUM) for dinitrogen molecules ( N 2 ) were examined at 298 K. The intensive IR absorption band observed at 2299 cm-' was attributed to the NZ species strongly adsorbed on CUM. The interaction of NZ with CUM is explored using adsorption calorimetry, X-ray absorption fine structure (XAFS), electron spin resonance (ESR), and photoemission spectroscopy. The differential heat and entropy of adsorption for N2 on CUM were 60 kJ mol-' and 60 J K-' mol-' at the initial stage of adsorption, respectively, and those for NZ on NaM (sodium-type mordenite) gave the values of 32 kJ mol-' and 130 J K-' mol-', revealing that the N2 molecules are in the localized state resulting from the strong interaction with CUM. The monolayer capacity is estimated to be 4.12 cm3 g-' for NZ on CUM-150, which gives a value of 0.22 for the Nz/Cu ratio. XAFS and emission data for CUM degassed at 873 K exhibit pair bands at 8.983 and 8.994 keV and 18 700 and 20 800 cm-I, respectively. The former pair band is assigned to the 1s-4p transition, and the latter pair band is assigned to the 3d94s1-3dl0 transition. It is also found that the ESR band intensity for Cu(I1) decreases with increasing pretreatment temperature. These spectral data are reasonably explained by assuming the presence of Cu(1) species in mordenite. It is proved from the emission data that the adsorption site including Cu(1) species easily formed by heat treatment at 873 K in vacuo is effective for N2 adsorption. Such easy conversion of Cu(II) to Cu(1) may be due to the spatial distribution of ion-exchanged sites on mordenite. The appearance of a strong IR band at 2299 cm-' is due to the adsorption of N2 on the Cu(1) species and to the induction of a transition moment by the strong field of this site. Although a rather high value of heat of adsorption might suggest chemisorption, it is made plausible that this type of N2 adsorption is physisorption.

Copper ions are exchanged in mordenite in amounts in excess of the value expected from stoichiometric considerations in the process of repeated ion-exchange of sodium ions in mordenite with copper ions. This is not the case for nickel and calcium ions used as exchanger ions. A series of experiments was designed to elucidate the state of excessively ion-exchanged copper in mordenite. DRS and EPR analyses together with XANES spectra revealed that the oxidation state of copper ion in mordenite is divalent in each exchange stage. IR, EPR, XANES and EXAFS studies provided evidence for the existence of a tetragonal hy!roxy-bridged polymer of copper !ens in excessively ion-exchanged mordenite; the Cu-0 bond length is 1.97 A and the Cu-Cu distance is 3.05 A. This polymer species exhibited IR absorption bands near 3350 and 930 cm-' for OH stretching and MOH bending vibrations of bridged species, respectively. The difference in exchange behaviour of divalent metal ions is interpreted in terms of the difference in the magnitude of their hydrolysis constants.

The peculiar feature of copper ion-exchanged mordenite in dinitrogen (N 2 ) adsorption has been investigated through the measurements of infrared (IR) and emission spectra (ES) and X-ray absorption fine structure (XAFS). IR spectra provided the definitive evidence for the existence of at least two kinds of adsorption sites on the 873 K-treated copper ion-exchanged mordenite; the absorption bands centered at 2160 and 2150 cm -1 appeared when CO molecules were adsorbed. The adsorbed species assigned to the former band was desorbed at 573 K in Vacuo and that to the latter one at 473 K. It was found that the site responsible for the latter band acts as effective sites for N 2 adsorption. XAFS spectra also showed new bands due to the CO adsorption on copper ion at 1.48 Å, 2.52 Å, and 8.981 keV, together with bands at 1.85 Å and 8.993 keV. The former set of bands was concomitant with the appearance of an IR band at 2150 cm -1 due to the adsorbed CO species. The two bands (at 8.981 and 8.993 keV) observed in the XAFS spectra for the CO-adsorbed sample are explained in terms of the formation of a planar three-or four-coordinate site through the reaction of copper ions with CO molecules. CO adsorption also caused a significant shift of the emission band from 470 to 430 nm. This band reverted to the original position by evacuating the sample at 473 K, accompanying a liberation of CO. This makes possible the interpretation that the adsorption site responsible for respective bands at 2150 cm -1 in IR, at 430 nm in ES, and at 8.981 keV in XAFS spectra through the interaction with CO molecules is effective for N 2 adsorption at ambient temperature.

An x-ray absorption fine-structure (XAFS) spectroscopy beamline, BL01B1, was installed at a bending magnet source at SPring-8 and has been open to users since October 1997. It was designed for XAFS experiments covering a wide energy range. Position tables and automatical control programs were established to adjust the x-ray optics and achieve the designed performance of the beamline under each experimental condition. This has enabled conventional XAFS measurements to be made with a good data quality from 4.5 to 110 keV. Keywords: XAFS; high-energy; beamlines.143 radiation light will be reported elsewhere. The results show that the target specifications for the measured beam have almost been completely achieved except for sagittal focusing: a photon flux of 109-10 ~ phs/s with AE/E of <2x 104, a vertical beam size focused by a mirror of < 0.2 mm, and a ratio of the higher harmonics contaminant of < 10 .5 with mirrors.To achieve the designed performance of the beamline in a wide energy range, the beamline optics should be adjusted to the optimal position for each experiment. Because rearranging the monochromator and/or mirrors involves the realignment of many components, such rearranging can be done a few times per day. To achieve quick and easy adjustment, we prepared tables at the positions of the optical components and developed automatic control programs. This report gives an overview of the beamline status and some representative results highlighting the performance of BL01B 1.

Recently many endohedral metallofullerenes such as M@C 74 , M@C 80 , and M@C 82 (M: metal atom) have been successfully isolated by the high performance liquid chromatography (HPLC) technique. 1-5 Some M@C 60 were prepared in primary soots by an arc-heating or a laser-vaporization method, 6-9 but the isolation of M@C 60 has not yet been achieved because of the difficulties in extraction; only the extraction of Ca@C 60 with pyridine has been reported so far. 10,11 Recently we found that aniline is a suitable extraction solvent for Ca@C 60 and Sr@C 60 . 12 For the isolation of M@C 60 by an HPLC technique it is important to find a suitable extraction solvent for M@C 60 . In the present study, we report the successful extraction of Y@C 60 , Ba@C 60 , La@C 60 , Ce@C 60 , Pr@C 60 , Nd@C 60 , and Gd@C 60 with aniline under an air atmosphere.The soots containing M@C 60 (M: Y, Ba, La, Ce, Pr, Nd and Gd) were prepared by the arc-heating of the M x O y /graphite (M x O y : x ) 2 and y ) 3 except for BaO, CeO 2 , and Pr 6 O 11 ) rods (Toyo Tanso; M concentration: 0.8 mol % except for Ba (0.3 mol %)) at 25 V and 80 A under 100 T of He atmosphere. We then tried 48 solvents 13 to extract Ca@C 60 , but had success only with aniline and pyridine. Therefore the extraction of M@C 60 was tried with aniline (Wako Pure Chemicals: GR) as well as three representative solvents of benzene, toluene

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Endohedral metallofullerene Ca@C60 has been prepared by archeating of graphite rod containing calcium oxide, CaO, and extracted by pyridine under the oxygen-free condition. The laser desorption time-of-flight (LD-TOF) mass spectrum of the pyridine solution exhibits five main peaks due to C60+, Ca@C60+, C70+, Ca@C70+, and C74+. It has been found that Ca@C60 can be extracted only under the atmosphere of degassed pyridine owing to its high oxygen-sensitivity.