Resonant Raman scattering from single crystals (Ph4P)(2)center dot C-60 center dot Y, where Y = Cl, Br, I

We report a Raman scattering study of (Ph4P)(2). C-60. Y single crystal (Y = Cl, Br and I). The resonant character of the Raman scattering has been de monstrated by measurements over a large excitation range: 514.5-1064 nm. In the Raman spectrum the enhanced low-frequency H-g modes excited at 1064 nm are broadened and down shifted. Each Hg band is deconvoluted into five com ponents. The role of the electron-molecular vibration coupling on the pecul iar profile of the H-g modes is discussed. (C) 1999 Elsevier Science Ltd. A ll rights reserved.