Raman spectra are presented for the single bonded dimeric fullerene (C-60)2 and compared to optical spectra and Raman spectra of the isostructural and isoelectronic heterofullerene (C59N)2. The spectra of both materials exhibit strong correlations with respect to splitting, line position, and line intensity. This holds for non resonant excitation with blue and green lasers as well as for the strong resonances observed with red lasers. The latter observation is consistent with a downshift for the electronic transition energies as compared to C60. The absorption edge of thin films of (C59N)2 was found at 1.4 eV. The three intercage modes were observed at 82, 103, and 111, and at 88, 98, and 106 cm-1 for (C59N)2 and (C-60)2, respectively. A surprising difference was found for the position of the pentagonal pinch modes in the two materials as they were observed at 1461 and at 1451 cm-1, for (C59N)2 and (C-60)2, respectively. This is interpreted as a consequence of some characteristic differences in the electronic structure of the two compounds.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics