Vibrational spectroscopy study and ab initio calculation on ZnMoO4 system

Abstract This report presents the results of experimental and theoretical Raman and infrared vibrational spectroscopic studies on the triclinic phase of zinc molybdate α-ZnMoO4 polycrystals. The assignments of the Raman and infrared modes were predicted using first-principle calculation through density functional perturbation theory (DFPT). Additionally, a theoretical study of the electronic properties of ZnMoO4 in relation to both the band structure and the associated projected density of states (PDOS) was performed by using first-principle calculations under the local density approximation (LDA). ZnMoO4 presents an indirect band-gap from the gamma point on the valence band to the Y point on the conduction band. The calculated electronic gap is in line with the well-known trend of DFT-LDA underestimation of band gap, confirming that the ZnMoO4 crystal is a semiconductor compound with an indirect band-gap of about 3.35 eV.