Laser-induced transformation of Li4C60 and Na4C60 polymers into metallic monomeric fulleride phases

Mingguang Yao (1) , Vittoria Pischedda (1) , Thomas Wågberg (2) , Bertil Sundqvist (2) , Sylvie Le Floch (1) , Alfonso San Miguel (1)

1 LPMCN - Laboratoire de Physique de la Matière Condensée et Nanostructures
2 Umeå University, Sweden

We demonstrate that laser irradiation on the narrow-gap insulator Li 4 C 60 and Na 4 C 60 polymers results in metallic monomeric structures, having the same Raman features as metallic fcc K 3 C 60 and Rb 3 C 60 , with orientationally disordered C 3À 60 anions stable at ambient conditions. The Raman Ag(2) mode indicates that a single phase was obtained. Additionally, a monomeric A 4 C 60-type phase (A = K, Rb) is observed in Na 4 C 60 after irradiation. The electron-phonon coupling constants derived from Raman modes of C 3À 60 fullerides is found to be higher than that of C 4À 60 fullerides, agreeing with the trend found in heavy alkali fullerides. We propose possible structures of the metallic phases.

Domaines: Matière Condensée [cond-mat]

Mingguang Yao, Vittoria Pischedda, Thomas Wågberg, Bertil Sundqvist, Sylvie Le Floch, et al.. Laser-induced transformation of Li4C60 and Na4C60 polymers into metallic monomeric fulleride phases. Chemical Physics Letters, 2010, 489 (1-3), pp.64-68. ⟨10.1016/j.cplett.2010.02.009⟩. ⟨hal-04015261⟩