Investigation of the polymerization mechanism of ferrocene doped C60 under high pressure and high temperature.

In situ high pressure and high temperature (HPHT) study has been carried out on C60/ferrocene (Fc) in order to detect the process of polymerization and reveal the polymerization mechanism. Pristine C60 was also studied under same conditions for comparison. In both cases, similar types of polymers can be observed after pressure and temperature release, but with different fractions, i.e. a larger amount of 2D polymers were formed in pure C60, while more branch-like polymers were synthesized in C60/Fc, although the most fraction of the polymers is still 1D chain-like polymer in both of the materials. The polymers formed in C60 can be detected both during the "up" run (pressure and temperature increase) and the "down" run (pressure and temperature decrease), while in C60/Fc, the polymers can only be synthesized in the "down" run. The differences between the two cases were attributed to the different initial lattice structures of the two materials and the confinement effect of the dopant. The polymerization mechanism on C60/Fc under HPHT was also revealed in this work.