title: Raman effect in icosahedral boron-rich solids.
abstract: We present Raman spectra of numerous icosahedral boron-rich solids having the structure of α-rhombohedral, β-rhombohedral, α-tetragonal, β-tetragonal, YB66, orthorhombic or amorphous boron. The spectra were newly measured and, in some cases, compared with reported data and discussed. We emphasize the importance of a high signal-to-noise ratio in the Raman spectra for detecting weak effects evoked by the modification of compounds, accommodation of interstitial atoms and other structural defects. Vibrations of the icosahedra, occurring in all the spectra, are interpreted using the description of modes in α-rhombohedral boron by Beckelet al. The Raman spectrum of boron carbide is largely clarified. Relative intra- and inter-icosahedral bonding forces are estimated for the different structural groups and for vanadium-doped β-rhombohedral boron. The validity of Badger's rule is demonstrated for the force constants of inter-icosahedral B-B bonds, whereas the agreement is less satisfactory for the intra-icosahedral B-B bonds.
authors.affiliation: Institute of Physics, University Duisburg-Essen, D-47048 Duisburg, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Werheit
authors.affiliation: I.N. Frantsevich Institute for Problems of Materials Science of NASU, 03142 Kiev, Ukraine.
authors.forename: Volodymyr
authors.initials: V
authors.lastname: Filipov
authors.affiliation: Institute of Physics, University Duisburg-Essen, D-47048 Duisburg, Germany; Present address: Pirelli Deutschland GmbH, D-64747 Breuberg.
authors.forename: Udo
authors.initials: U
authors.lastname: Kuhlmann
authors.affiliation: Max-Plank-Institute for Chemical Physics of Solids, D-01187 Dresden, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Schwarz
authors.affiliation: Max-Plank-Institute for Chemical Physics of Solids, D-01187 Dresden, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Armbrüster
authors.affiliation: Max-Plank-Institute for Chemical Physics of Solids, D-01187 Dresden, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Leithe-Jasper
authors.affiliation: National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
authors.forename: Takaho
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-01, Japan.
authors.forename: Iwami
authors.initials: I
authors.lastname: Higashi
authors.affiliation: Institte of Chemistry, Uppsala University, S-75121 Uppsala, Sweden.
authors.forename: Torsten
authors.initials: T
authors.lastname: Lundström
authors.affiliation: Ioffe Physical-Technical Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia.
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Gurin
authors.affiliation: Ioffe Physical-Technical Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia.
authors.forename: Maria M
authors.initials: MM
authors.lastname: Korsukova
keywords: >YB66; Raman scattering; amorphous boron; icosahedral boron-rich solids; orthorhombic boron structures; α-rhombohedral boron; α-tetragonal boron; β-rhombohedral boron; β-tetragonal boron