…mation as (⃗ ) ∑ ( ) ⃗q ⃗ ⃗ ⃗ ⃗ = ei q· l ⃗b ⃗q (1.3) This reduces the periodic system with infinite unit cells to just one cell with dis⃗ (⃗q ). Therefore we need to solve a standard small vibration problem placement U ⃗b within one cell, but keeping in mind the ⃗q dependence in…

…Gibbs emphasized the generality of thermodynamic principles to include material systems of all kinds [4]. His pioneering insights slowly brought scientific unity to the practices of chemical metallurgy, by uncovering the underlying principles in the centuries of collected physica…

…so interact with magnetic excitations, impacting the thermodynamics of magnetic systems, such as the phase transitions of the Ni2 MnGa magnetic shape memory system [12]. From experimental measurements of phonons in materials at high temperatures, we observe that these phonon inte…

…D) measurements storages. In particular, the magnesium hydride is an attractive system at room temperature the transition α → γ, but at much higher pressure for the hydrogen storage, as it is one of the systems with a high hy- of 9 GPa [7]. Moses et al. built the P-T phase diagra…