title: Fullerene quantum gyroscope.
abstract: We report the observation of quantized rotational states of a diatomic C2 unit in solid endohedral fullerene C(2)Sc(2)@C(84). The rotational transitions induce a periodic line pattern in the low energy Raman spectrum. The rotational constant B and the C-C distance were found to be 1.73 cm(-1) and 0.127 nm, respectively. Density functional calculations revealed an intrinsic rotational barrier of the order of only a few meV for the C2 unit. The Schrödinger equation involving the potential barrier was solved and the Raman tensor matrix elements were calculated, yielding good quantitative agreement with the experiment. To our best knowledge this is the first intrinsic rotational spectrum of a diatomic plane molecular rotor.
authors.affiliation: Institut für Materialphysik der Universität Wien, Wien, Austria.
authors.forename: M
authors.initials: M
authors.lastname: Krause
authors.forename: M
authors.initials: M
authors.lastname: Hulman
authors.forename: H
authors.initials: H
authors.lastname: Kuzmany
authors.forename: O
authors.initials: O
authors.lastname: Dubay
authors.forename: G
authors.initials: G
authors.lastname: Kresse
authors.forename: K
authors.initials: K
authors.lastname: Vietze
authors.forename: G
authors.initials: G
authors.lastname: Seifert
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.forename: H
authors.initials: H
authors.lastname: Shinohara