ArC60 synthesized by heating primarily C60 (with trace amounts of C70 under a high pressure of argon gas,was purified by high-performance liquid chromatography (HPLC) and examined by Fourier transform mass spectrometry (FTMS). The sample, which consisted of 0.1% ArC60, was dissolved in toluene and separated with HPLC using a COSMOSIL 5PYE column as the stationary phase and toluene as the eluent (UV detection). ArC60 was enriched by a factor of about 400 relative to the starting material. ArC60 was also examined by X-ray photoelectron spectroscopy (XPS) but was found to be sensitive to radiation damage and subsequent depletion. Low-energy collisional dissociation of Ar$+$/ C60+ in the FTMS yields primarily C58+, generated by loss of the argon atom and C2. The ionization potential of Ar$+$/C60 was bracketed by charge-exchange reactions and was found to be between 7.53 and 7.8 eV, which is indistinguishable from that of C60 (7.65 eV).
Dicamillo, B. A., Hettich, R. L., Guiochon, G., Compton, R. N., Saunders, M., Jimenez-Vazquez, H. A., Khong, A., & Cross, R. J. (1996). Enrichment and characterization of a noble gas fullerene: ArC60. Journal of Physical Chemistry, 9197-9201. https://doi.org/10.1021/jp960049k