A density functional theory study of Raman modes of cadmium hexathiohypodiphosphate (CdPS₃)

Raman scattering investigations based on density functional theory (DFT) calculations were performed to explore the vibrational modes of a cadmium hexathiohypodiphosphate CdPS₃ single crystal. The calculations were performed to obtain the Raman spectra for the cadmium hexathiohypodiphosphate atoms to study the size dependence. Several vibrational modes indicating stretching and bending features related to Cd, S and P atoms were observed. Modifications of the frequency and intensity of different Raman modes with an increase in the number of atoms in CdPS₃ were discussed in detail. Hydrogen atoms were added in order to make the closed shell configuration and saturate the CdPS₃ as per the requisite for calculating the Raman spectra. This produced some additional modes of vibration related to hydrogen atoms. Band gap and formation energy were also calculated. The results generated are found to be in close agreement with the experimental values.