Anion Reorientations in the Superionic Conducting Phase of Na2B12H12

Published

August 7, 2014

Author(s)

Kristina Verdal, Terrence J. Udovic, Vitalie Stavila, Wan Si NMN Tang, John J. Rush, Alexander V. Skripov

Abstract

Quasielastic neutron scattering (QENS) methods were used to characterize the reorientational dynamics of the dodecahydro-closo-dodecaborate (B₁₂H₁₂6u2-^0 anions in the high-temperature, superionic conducting phase of na₂B₁₂H6d12^. The icosahedral anions in this disordered cubic phase were found to undergo rapid reorientational motions, on the order of 10¹¹ jumps s^-1 above 530 K, consistent with previous NMR measurements and neutron elastic-scattering fixed-window scans. QENS measurement as a function of the neutron momentum transfer suggest a reorientational mechanism dominated by small-angle jumps around a single axis. The results show a relatively low activation energy for orientation of 259 meV (25Kj/mol).

Citation

Journal of Physical Chemistry C

Volume

118

Issue

31

Pub Type

Journals

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Keywords

Dodecahydro-closo-Dodecaborate Anion, Superionic Conductivity, Hydrogen Storage, Quasielastic Neutron Scattering, Reorientational Dynamics

Citation

Verdal, K. , Udovic, T. , Stavila, V. , Tang, W. , Rush, J. and Skripov, A. (2014), Anion Reorientations in the Superionic Conducting Phase of Na₂B₁₂H₁₂, Journal of Physical Chemistry C, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=916284 (Accessed May 8, 2024)