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.