  We investigate crystalline thermodynamic stable lithium silicides phases
(LixSiy) with density functional theory (DFT) and a force-field method based on
modified embedded atoms (MEAM) and compare our results with experimental data.
This work presents a fast and accurate framework to calculate thermodynamic
properties of crystal structures with large unit cells with MEAM based on
molecular dynamics (MD). Mechanical properties like the bulk modulus and the
elastic constants are evaluated in addition to thermodynamic properties
including the phonon density of states, the vibrational free energy and the
isochoric/isobaric specific heat capacity for Li, Li12Si7, Li7Si3, Li13Si4,
Li15Si4, Li21Si5, Li17Si4, Li22Si5 and Si. For a selected phase (Li13Si4) we
study the effect of a temperature dependent phonon density of states and its
effect on the isobaric heat capacity.
