On the origin of the 1100 cm −1 Raman band in amorphous and nanocrystalline sp 3 carbon

Recently, the correlation between the 1100 cm −1 Raman band and the sp 3 fraction in amorphous or nanocrystalline carbon films was unambiguously demonstrated. From theoretical and experimental results on carbon-assembled materials, an explanation about the 1100 cm −1 Raman band origin is given. The difficulty to detect this band except in near-resonance condition is also discussed.