Structural, optoelectronic, infrared and Raman spectra from first principles calculations of γ-Cd(OH)2

We have investigated the physical properties of the cadmium hydroxide polymorph γ-Cd(OH)2 using density-functional theory (DFT) considering both the local density and generalized gradient approximations, LDA and GGA, respectively. The electronic band structure, the electronic density of states, the dielectric function and the optical absorption are calculated. A comparison reveals good agreement of the calculated lattice parameters with experimental results. A direct band gap E(Γ→Γ)=1.70eV (1.53 eV) was obtained within the GGA (LDA) level of calculation. The vibrational normal modes as well as the Raman and infrared spectra of γ-Cd(OH)2 were obtained and assigned.