Thermal stability of Li@C-60

The thermal stability of purified endohedral Li@C-60 has been studied. Ther e are two endohedral compounds produced from Li+ irradiated C-60 that have slightly different stabilities. The endohedral species decay at elevated te mperatures on a time scale of a few hours when in solution and exposed to l ight and air. The dry, purified material has a higher thermal stability and can be sublimed in vacuum to produce thin films of pure endohedral fullere nes.