Phosphates branching effect on the structure, linear and NLO properties of linear phosphazenes

Abstract In this paper, we studied the structure, dipole moment, polarizability, and static first hyperpolarizability of linear phosphazenes. The relationship between the nonlinear optical (NLO) properties and the energy gaps was also taken into account. The structure of these phosphazenes has been performed using the B3LYP, ωB97X–D and M06–2X functionals. The linear and NLO properties of these compounds have shown selective responses to the different DFT levels that are in good agreement with the experimental values of similar compounds. The ωB97X–D functional gives a high static first hyperpolarizability compared to the B3LYP and M06–2X levels. An inverse relationship has been obtained between the HOMO–LUMO gaps and β tot . This theoretical study confirms the suitability of these phosphazenes for optoelectronic and optical devices.