On the Synthesis Conditions of N and N₂ Endohedral Fullerenes

Abstract

The glow discharge at low pressure, under nitrogen atmosphere, is an easy method to synthesize nitrogen encapsulated fullerenes. We present here the results concerning our attempts to optimize the synthesis conditions by this method as well as basic characterization of the obtained products, namely N@C₆₀ and N@C₇₀ together with the molecular counterparts N₂@C₆₀ and N₂@C₇₀. Changes in pressure, voltage discharge and temperature indicated the optimum yield for N@C₆₀ in our case, which was about 0.0025%, was obtained at 650°C, 1 Torr, 850 V and 1 to 2 mA discharge. In this paper we discuss the HPLC separation of these products and the behavior of N₂ in the C₆₀ cage.

Keywords:

• Fullerene
• nitrogen
• endohedralfullerene
• synthesis
• glow discharge

Acknowledgments

We thank A. Weidinger and W. Harneit of Hahn‐Meitner Institute in Berlin for their help concerning this work.