High resolution Raman and neutron investigation of Mg(BH₄) ₂ in an extensive temperature range

Raman spectra of Mg(BH₄)₂ have been measured in an extensive temperature range, from 15 to 473 K. Taking into account the high temperature conversion from the a to the β phase, we have observed evident signatures of this phase transition and determined the Raman vibrational spectrum of each phase. The neutron scattering spectra of the β phase sample were also recorded. The present experimental results have been compared to the density functional theory calculations available in the literature, and a substantial agreement has been found.