TY - JOUR
T1 - Hydrogen dynamics in β-Mg(BH4)2 on the picosecond timescale
AU - Silvi, Luca
AU - Röhm, Eva
AU - Fichtner, Maximilian
AU - Petry, Winfried
AU - Lohstroh, Wiebke
N1 - Publisher Copyright:
© 2016 the Owner Societies.
PY - 2016
Y1 - 2016
N2 - A quasielastic neutron scattering study on β-Mg(BH4)2 has been performed to investigate the hydrogen dynamics on the picosecond time-scale. Both vibrational and rotational motions of the [BH4]- tetrahedra contribute to the signal at low energy transfers. A comprehensive analysis of the elastic and quasielastic incoherent structure factors allowed the separation of different parts. Below 200 K, vibrations and rotations (around the C2 or C3 symmetry axis of the [BH4]- tetrahedra) are well separated. Above that temperature, a transition is observed in the vibrational part, and the spectral weight is shifted towards the quasielastic region. The dynamic transition is not accompanied by any structural phase change but we suggest that it is correlated with the anomalous thermal expansion that has been reported for β-Mg(BH4)2 [Filinchuk, et al., Chem. Mater., 2009, 21, 925].
AB - A quasielastic neutron scattering study on β-Mg(BH4)2 has been performed to investigate the hydrogen dynamics on the picosecond time-scale. Both vibrational and rotational motions of the [BH4]- tetrahedra contribute to the signal at low energy transfers. A comprehensive analysis of the elastic and quasielastic incoherent structure factors allowed the separation of different parts. Below 200 K, vibrations and rotations (around the C2 or C3 symmetry axis of the [BH4]- tetrahedra) are well separated. Above that temperature, a transition is observed in the vibrational part, and the spectral weight is shifted towards the quasielastic region. The dynamic transition is not accompanied by any structural phase change but we suggest that it is correlated with the anomalous thermal expansion that has been reported for β-Mg(BH4)2 [Filinchuk, et al., Chem. Mater., 2009, 21, 925].
UR - http://www.scopus.com/inward/record.url?scp=84971223732&partnerID=8YFLogxK
U2 - 10.1039/c6cp00995f
DO - 10.1039/c6cp00995f
M3 - Article
AN - SCOPUS:84971223732
SN - 1463-9076
VL - 18
SP - 14323
EP - 14332
JO - Physical Chemistry Chemical Physics
JF - Physical Chemistry Chemical Physics
IS - 21
ER -