High pressure photoinduced polymerization of the orthorhombic polymeric phase of C60

The stability of the linear orthorhombic polymer of C60 as a function of pressure has been studied by Raman scattering and X-ray measurements. The in situ Raman study shows an irreversible transition to a new phase occurring at pressures as low as ∼0.3 GPa. The specimens treated at pressure up to 3 GPa without laser irradiation do not show any structural changes after pressure release. The Raman spectrum of the new phase differs from those of the known 2D polymerized phases of C60. These data indicate that the simultaneous application of pressure and laser irradiation results in pressure photoinduced polymerization of the pristine polymeric chains of C60 thus transforming it to a new polymeric phase of C60.