title: Pressure-induced hydrogen bond symmetrization in iron oxyhydroxide.
abstract: Under high pressures the hydrogen bonds were predicted to transform from a highly asymmetric soft O-H···O to a symmetric rigid configuration in which the proton lies midway between the two oxygen atoms. Despite four decades of research on hydroxyl containing compounds, pressure induced hydrogen bond symmetrization remains elusive. Following single crystal x-ray diffraction, Mössbauer and Raman spectroscopy measurements supported by ab initio calculations, we report the H-bonds symmetrization in iron oxyhydroxide, FeOOH, resulting from the Fe(3+) high-to-low spin crossover at above 45 GPa.
authors.affiliation: School of Physics and Astronomy, Tel Aviv University, 69978, Tel Aviv, Israel.
authors.forename: Weiming
authors.initials: W
authors.lastname: Xu
authors.forename: Eran
authors.initials: E
authors.lastname: Greenberg
authors.forename: Gregory Kh
authors.initials: GKh
authors.lastname: Rozenberg
authors.forename: Moshe P
authors.initials: MP
authors.lastname: Pasternak
authors.forename: Elena
authors.initials: E
authors.lastname: Bykova
authors.forename: Tiziana
authors.initials: T
authors.lastname: Boffa-Ballaran
authors.forename: Leonid
authors.initials: L
authors.lastname: Dubrovinsky
authors.forename: Vitali
authors.initials: V
authors.lastname: Prakapenka
authors.forename: Michael
authors.initials: M
authors.lastname: Hanfland
authors.forename: Olga Yu
authors.initials: OY
authors.lastname: Vekilova
authors.forename: Sergei I
authors.initials: SI
authors.lastname: Simak
authors.forename: Igor A
authors.initials: IA
authors.lastname: Abrikosov