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Lithium boro-hydride LiBH4 II. Raman spectroscopy
|Published in||Journal of Alloys and Compounds. 2002, vol. 346, no. 23, p. 206-210|
|Abstract||Polycrystalline LiBH4 has been studied by Raman spectroscopy in the temperature interval 295–412 K and the frequency range 2700–130 cm−1. The Raman active modes are consistent with the presence of a (BH4)− ion having a distorted tetrahedral configuration. As the temperature is increased the sudden disappearance of mode splitting points to the onset of a structural phase transition that leads to a higher local symmetry of the (BH4)− tetrahedron. The transition occurs at 384 K, is of first-order and has a hysteresis of about 8 K. A strong and discontinuous broadening of bands remaining after the transition suggests the onset of large vibrational amplitudes of the (BH4)− tetrahedra about their trigonal axis.|
|Keywords||Hydrogen storage materials — Metal hydrides — Crystal structure — Raman spectroscopy — Phase transition|
|Research group||Groupe Hagemann|
|GOMES, Sandrine, HAGEMANN, Hans-Rudolf, YVON, Klaus. Lithium boro-hydride LiBH4 II. Raman spectroscopy. In: Journal of Alloys and Compounds, 2002, vol. 346, n° 23, p. 206-210. doi: 10.1016/S0925-8388(02)00668-0 https://archive-ouverte.unige.ch/unige:3229|