Fullerene C70 as a Nanoflask that Reveals the Chemical Reactivity of Atomic Nitrogen.

To investigate the intrinsic reactivity of atomic nitrogen, which had previously been accomplished only by examining its decay in the gas phase using special equipment, a nitrogen atom was inserted into a series of molecule-encapsulating C60 and C70 fullerenes. Among the studied endofullerenes, H2 @C70 was able to encapsulate an additional nitrogen atom within the fullerene cage under radiofrequency plasma conditions. The product was analyzed by ESR spectroscopy and mass spectrometry in solution, which revealed that the nitrogen atom with a quartet ground state does not react but weakly interact with the H2 molecule, thus demonstrating the utility of such fullerenes as "nanoflasks".