title: Dispersion Relation of an OH-Stretching Vibration from Inelastic X-Ray Scattering.
abstract: We show that recent advances now allow us to measure the wave vector dependence of OH-stretching frequencies at energies around 400 meV by inelastic x-ray scattering using ID28@ESRF. We found a large, unexpected dispersion when we measured the dispersion relations of the hydrogen stretching frequencies of diaspore, alpha-AlOOH, where the hydrogen atoms participate in a hydrogen bond of intermediate strength. We can account for this behavior with density functional perturbation theory calculations and a simple model based on H-H interactions.
authors.affiliation: Geowissenschaften, Goethe-Universität, Altenhoeferallee 1, D-60438 Frankfurt a.M., Germany. b.winkler@kristall.uni-frankfurt.de
authors.forename: Björn
authors.initials: B
authors.lastname: Winkler
authors.forename: Alexandra
authors.initials: A
authors.lastname: Friedrich
authors.forename: Dan J
authors.initials: DJ
authors.lastname: Wilson
authors.forename: Eiken
authors.initials: E
authors.lastname: Haussühl
authors.forename: Michael
authors.initials: M
authors.lastname: Krisch
authors.forename: Alexei
authors.initials: A
authors.lastname: Bosak
authors.forename: Keith
authors.initials: K
authors.lastname: Refson
authors.forename: Victor
authors.initials: V
authors.lastname: Milman