The semiconductors of zinc blend structure are promising candidate materials for numerous experimental and theoretical investigations. In recent years, considerable effort has been made to study the lattice infrared absorption spectrum of II-VI compounds, renewed interest has been taken in CdTe owing to its relatively high electro - optic coefficient in the near infrared. In addition, its nonlinear response to two-phonon absorption in the infrared region is of interest because the material is transparent in this spectral region.