Theoretical insights into the nonlinear optical properties of cyclotriphosphazene (P3N3Cl6), tris(4–hydroxyphenyl) ethane and their various inorganic–organic hybrid derivatives

With the rapid developments of computational methods, now it is effective and efficient to predict properties and underlying reasons at different stages. In this work, we systematically investigated hexachlorocyclotriphosphazene, tris(4–hydroxyphenyl) ethane and their various inorganic–organic hybrid derivatives for dipole moment, polarizability and static first hyperpolarizability. The relation between the nonlinear optical (NLO) properties and the energy gaps were also considered. The geometries of these inorganic–organic hybrid derivatives at different substitution positions have been performed using the B3LYP functional. The ωB97X–D and B3LYP functionals give the high static first hyperpolarizability compared to the CAM–B3LYP and M05–2X levels. Inverse relation has been obtained between the HOMO–LUMO gaps and the hyper-Rayleigh scattering (HRS) first hyperpolarizability $${eta }_{ ext{HRS}}$$ . This theoretical study reveals underlying changes in the design structures, and shift in properties will provide better understanding and may grab the attention of researchers to study cross-linkable organocyclotriphosphazenes for NLO application.