We present a calculation of the Hg phonon self-energy for a model of A3C60 (A= K, Rb). The orientational disorder of the C60 molecules is included, and the lowest order self-energy diagram is considered. The calculations illustrate that due to the violation of momentum conservation by the orientational disorder, Raman scattering can measure the decay of a phonon in an electron-hole pair, allowing the estimate of the electron-phonon coupling from such experiments. Comparison with experimental line shapes further provides support for a local correlation of the molecular orientations, with neighboring molecules preferentially having orientations differing by a 90 degree rotation.
@article{arxiv.cond-mat/9902191,
title = {Phonon line shape in disordered A3C60 (A= K, Rb)},
author = {J. E. Han and O. Gunnarsson and V. Eyert},
journal= {arXiv preprint arXiv:cond-mat/9902191},
year = {2009}
}
Comments
7 pages, latex2e, 3 eps figure, additional material avalable at http://www.mpi-stuttgart.mpg.de/docs/ANDERSEN/fullerene/