Local structure investigation of β-Ni(OH)2 under pressure using combined Raman and Ni K-edge extended x-ray absorption fine structure studies

Research output: Contribution to journalJournal article – Annual report year: 2017Researchpeer-review

Without internal affiliation

  • Author: Marini, C.

    CELLS-ALBA, Spain

  • Author: Joseph, Bertrand

    Sincrotrone Trieste, Italy

  • Author: Caramazza, S.

    University of Rome La Sapienza, Italy

  • Author: Capitani, F.

    University of Rome La Sapienza, Italy

  • Author: Bendele, M.

    University of Rome La Sapienza, Italy

  • Author: Kantor, Innokenty

    European Synchrotron Radiation Facility

  • Author: Lotti, P.

    Sincrotrone Trieste, Italy

  • Author: Mathon, O.

    European Synchrotron Radiation Facility, France

  • Author: Pascarelli, S.

    European Synchrotron Radiation Facility, France

  • Author: Postorino, P.

    University of Rome La Sapienza, Italy

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We present a combined high pressure Ni K-edge x-ray absorption and Raman spectroscopic investigation of β-Ni(OH)2. Extended x-ray absorption fine structure analysis reveals a progressive shrinking of the Ni-O and Ni-Ni bond distances with pressure. As pressure is increased, Raman data show a continuous hardening of the phonon modes associated with the vibration of Ni-O sublattice, whereas a systematic frequency softening is displayed by the hydroxyl (O-H) symmetric stretching mode. This contrasting behavior implies a gradual development of a lattice instability with pressure in nickel hydroxide. Under pressure hydrogen bonds become increasingly unstable mainly due to the displacement of H atoms around the Ni-O axis inducing a local-lattice instability may explain the structural, Raman and x-ray absorption results.
Original languageEnglish
JournalHigh Pressure Research
Volume37
Issue number1
Pages (from-to)1-10
Number of pages10
ISSN0895-7959
DOIs
Publication statusPublished - 2017
Externally publishedYes
CitationsWeb of Science® Times Cited: No match on DOI

    Research areas

  • High pressure, RAMAN, EXAFS

ID: 145210711