Raman cross section for the pentagonal-pinch mode in buckminsterfullerene C 60

Abstract

The Raman cross section for the pentagonal pinch mode of C 60 at 1469 cm −1 has been determined at a laser excitation wavelength λ L = 752.5 nm. The experimental value, dσ/ dΩ = (2.09 ± 0.29) × 10 −29 cm 2/ sr , is found to be in good agreement with predictions from an ab initio calculation based on density functional perturbation theory. A simple bond polarizability model with parameters obtained from hydrocarbon Raman measurements yields Raman intensities in C 60 within one order of magnitude of the experimental data.