File for each material includes parameters for the shear modulus per Ref.1, then the Einstein temperature (K) tabulated against mass density (g/cm3) and the Peierls barrier parameter fb and other basic parameters needed per Ref.2. The fv parameter gives the lattice type from which the numerical value is found from Table 1 in Ref.2.
For a few materials, a functional fit is used for the Einstein temperature
instead of a table.
The function used is almost the same as for shear modulus
θE(ρ) =
T0(ρ/ρref)p0 f(ρ)
+T1(ρ/ρref)p1 [1 - f(ρ)]
where
f(ρ) = exp(-μ/μt) and
μ = ρ/ρref - 1
with parameters ρref, T0, p0, μt,
T1, p1.