Isolation of CeLu2N@Ih-C80 Though a Non-Chromatographic, Two-Step Chemical Process and Crystallographic Characterization of the Pyramidalized CeLu2N within the Icosahedral Cage
Chemistry - European Journal
By combining two chemical methods of purification, 4 mg of purified CeLu2N@C80 was readily isolated from 500 mg of carbon soot extract without the use of recycling HPLC, a method which has previously been necessary to obtain pure samples of endohedral fullerenes. In stage 1, CeLu2N@C80 was selectively precipitated by virtue of its low first oxidation potential (+0.01 V) and the judicious choice of MgCl2 as the Lewis acid precipitant. For stage 2, we used a stir and filter approach (SAFA), which employed the electron-rich NH2 groups immobilized on silica gel to selectively bind residual endohedrals and higher cage fullerenes that were contaminants from stage 1. Crystallographic analysis of CeLu2N@C80 in the co-crystal CeLu2N@Ih-C80⋅Ni(octaethylporphyrin)⋅2(toluene) reveals that the Ih-C80 cage is present with a pyramidalized CeLu2N unit inside.
Steven Stevenson, H R. Thompson, K D. Arvola, K B. Ghiassi, M M. Olmstead, and A L. Balch (2015).
Isolation of CeLu2N@Ih-C80 Though a Non-Chromatographic, Two-Step Chemical Process and Crystallographic Characterization of the Pyramidalized CeLu2N within the Icosahedral Cage. Chemistry - European Journal.21 (29), 10362–10368.