ENRICHMENT AND CHARACTERIZATION OF A NOBLE-GAS FULLERENE - AR-AT-C-60

AT@C-60, synthesized by heating primarily C-60 (with trace amounts of C-70) under a high pressure of argon gas, was purified by high-perform ance liquid chromatography (HPLC) and examined by Fourier transform ma ss spectrometry (FTMS). The sample, which consisted of 0.1% Ar@C-60, w as dissolved in toluene and separated with HPLC using a COSMOSIL, 5PYE column as the stationary phase and toluene as the eluent (UV detectio n). AT@C-60 was enriched by a factor of about 400 relative to the star ting material. AT@C-60 was also examined by X-ray photoelectron spectr oscopy (XPS) but was found to be sensitive to radiation damage and sub sequent depletion. Low-energy collisional dissociation of Ar@C-60(+) i n the FTMS yields primarily C-58(+), generated by loss of the argon at om and C-2. The ionization potential of Ar@C-60 was bracketed by charg e-exchange reactions and was found to be between 7.53 and 7.8 eV, whic h is indistinguishable from that of C-60 (7.65 eV).