title: Raman spectroscopic study of the rare-earth fullerides Eu6-xSrxC60.
abstract: We present Raman spectroscopic studies of the isostructural and isoelectronic Eu(6-x)Sr(x)C(60) (x = 0, 3, 5, 6) and Ba(6)C(60) compounds. The Raman spectra of the Eu-based fullerides show dramatic changes compared to the pure alkaline-earth systems, including significant broadening, splitting and frequency shifts of the fivefold degenerate H(g) intramolecular modes of C(60). Moreover, the A(g)(2) mode exhibits an even larger downshift and a remarkable broadening. These findings are consistent with distortions of the C(60) molecular cages and a considerable electron-phonon coupling strength-strongly enhanced in the Eu containing systems-originating from the strong orbital hybridization between the metal atom and the C(60) molecule.
authors.affiliation: Department of Applied Sciences, Technological Educational Institute of Thessaloniki, 57400, Sindos, Greece. jarvan@eng.auth.gr
authors.forename: J
authors.initials: J
authors.lastname: Arvanitidis
authors.forename: D
authors.initials: D
authors.lastname: Christofilos
authors.forename: G A
authors.initials: GA
authors.lastname: Kourouklis
authors.forename: A
authors.initials: A
authors.lastname: Paloumpi
authors.forename: K
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authors.lastname: Papagelis
authors.forename: S
authors.initials: S
authors.lastname: Ves
authors.forename: Y
authors.initials: Y
authors.lastname: Iwasa
authors.forename: K
authors.initials: K
authors.lastname: Prassides