Raman study of the electron-phonon interaction in light alkali metal intercalated metallic fullerides
Mingguang Yao1, Vittoria Pischedda, Alfonso San Miguel
1Université de Lyon, Laboratoire PMCN, CNRS, UMR 5586, Villeurbanne, France. yaomg@jlu.edu.cn
Abstract:
By laser-irradiating polymeric Li(4)C(60) and Na(4)C(60), we have obtained pure monomeric metallic phases stable at ambient conditions. Based on a systemic Raman analysis, we have determined the electron-phonon coupling constant for both metallic phases. The e-p coupling constants of Li- and Na-intercalated metallic fullerides are smaller than those of superconductive K(3)C(60) and Rb(3)C(60) and comparable to or slightly higher than that of ambient-pressure non-superconductive Cs(3)C(60). We predict that Na-doped fulleride could exhibit superconductivity with T(c) ∼ 10 K. Much lower T(c) or even no superconductivity can be expected for the Li-doped fulleride which exhibits a strong Li(+)-C interaction. These results contribute to the understanding of superconductivity in light alkali metal intercalated fullerides.
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