Photoluminescence dynamics and spectra of C-60 and C-60(-) in VPI-5 molecular cages

Abstract

C60 incorporated in VPI-5 nanochannels shows anomalous upper-excited and anionic, as well as normal, fluorescence. The upper-excited fluorescence has the maximum at 440 nm and decays in 13 ps to give birth to the normal fluorescence having the maximum at 730 nm. The latter has the lifetime of 1400 ps, whereas the anionic fluorescence having the maximum at 760 nm decays on the timescale of 110 ps. Confinement effect in VPI-5 molecular nanocages brings in the formation of C60 - having a narrow ESR linewidth. It also increases the oscillator strength and fluorescence lifetimes of C60 and C60 -.