Neutron Scattering Study of the High-energy Graphitic Phonons in Superconducting CaC6
We present the results of a neutron scattering study of the high energy phonons in the superconducting graphite intercalation compound CaC{sub 6}. The study was designed to address hitherto unexplored aspects of the lattice dynamics in CaC{sub 6}, and in particular any renormalization of the out-of-plane and in-plane graphitic phonon modes. We present a detailed comparison between the data and the results of density functional theory (DFT). A description is given of the analysis methods developed to account for the highly-textured nature of the samples. The DFT calculations are shown to provide a good description of the general features of the experimental data. This is significant in light of a number of striking disagreements in the literature between other experiments and DFT on CaC{sub 6}. The results presented here demonstrate that the disagreements are not due to any large inaccuracies in the calculated phonon frequencies.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- Doe - Office Of Science
- DOE Contract Number:
- DE-AC02-98CH10886
- OSTI ID:
- 988790
- Report Number(s):
- BNL-93859-2010-JA; R&D Project: PO-011; KC0202010; TRN: US201019%%147
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Vol. 81, Issue 1; ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- English
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