Photoinduced transformation of luminescence centers in C60 crystals at high pressure

The influence of laser irradiation on the photoluminescence spectra of perfect C₆₀ crystals in the orientationally disordered phase is investigated. It is shown that irradiation of the crystals with low-power light for short durations at T=200 K produces radical changes in the luminescence spectrum. The pressure dependences of the spectral bands of the phototransformed and initial (without irradiation) spectra differ significantly, indicating a photoinduced structural transformation of the X centers responsible for the luminescence of C₆₀. The phototransformed C₆₀ crystals are stable against further exposure to light irradiation and pressure. Pis’ma Zh. éksp. Teor. Fiz. 70, No. 12, 784–788 (25 December 1999) Deceased.