Theoretical Calculations of Refractive Index of Synthesized One and Two Substituted Derivatives of Functionalized Bithiophene Compounds

In order to study the variation of electronic properties, a set of bithiophene derivatives has been ‎developed. Here, the effect of substitution on the aromaticity properties of some cyclic ‎bithiophene derivative compounds was investigated using theoretical calculations. Calculations ‎were performed at B3LYP/6-31+G (d,p) level; and calculated properties included energy, dipole ‎moment, total charge on sulfur atom, energy gap, hardness and dipole polarizability. ‎Experimental polarizability values were comparable with the theoretical values. Theoretical ‎refractive indices were obtained using average polarizability in Lorentz-Lorentz equation. The ‎results of comparison between theoretical and experimental refractive indices demonstrated that ‎the scaling factors for refractive index and polarizability were 0.99-1.14 and 0.98-1.28, ‎respectively. ‎