Optical properties of polyvalent metals in the solid and liquid state: aluminium

A semiphenomenological theory is proposed for the calculation of the frequency and temperature dependences of the optical properties of polyvalent metals. Utilizing the concept of parallel bands, the transverse optical conductivity is decomposed into a nearly-free-electron part and in an interband part. The theory needs only one fitting parameter, the unknown electron-electron scattering frequency above the Fermi energy. The complete set of optical quantities is calculated for aluminium for a large frequency range (0.01-50 eV) and from T=300 to 2000 K.