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Multi-phonon scattering and Ti-induced hydrogen dynamics in sodium alanate

Jorge Iniguez·T. Yildirim·T. J. Udovic·E. H. Majzoub·M. Sulic·C. M. Jensen
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Abstract

We use ab initio methods and neutron inelastic scattering (NIS) to study the structure, energetics, and dynamics of pure and Ti-doped sodium alanate (NaAlH_4), focusing on the possibility of substitutional Ti doping. The NIS spectrum is found to exhibit surprisingly strong and sharp two-phonon features. The calculations reveal that substitutional Ti doping is energetically possible. Ti prefers to substitute for Na and is a powerful hydrogen attractor that facilitates multiple Al--H bond breaking. Our results hint at new ways of improving the hydrogen dynamics and storage capacity of the alanates.

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Jorge Iniguez, T. Yildirim, T. J. Udovic, E. H. Majzoub, M. Sulic, C. M. Jensen. 2004-01-09. Multi-phonon scattering and Ti-induced hydrogen dynamics in sodium alanate. https://doi.org/10.1103/physrevb.70.060101

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