Chemical structure-optical property understanding in bisphenyls and substituted polycarbonates by molecular simulations: Role of polarizabilities and conformations

We present calculations of polarizability tensors, optical anisotropy of organic molecules, repeating units and polymer chains of several bisphenyls, bisphenol carbonates and polycarbonates with a variety of chemical substitutions.$^{1,2}$ Theoretical calculations of polarizabilities and optical birefringence of several newer structures having specific side-group substitutions which render low birefringence, not previously reported, is also shown here. Our method combines VOSRIS scheme$^{3}$, molecular geometry and conformations from force-field simulations and accurate anisotropic polarizability tensors. Aliphatic, aliphatic aromatic and cycloaliphatic substitutions reduce optical anisotropy in relation to bisphenol A polycarbonate. Calculated $\langle $\textit{$\gamma $}$^{2}\rangle $/$x$ of these structurally modified polycarbonates$^{2}$ follows linear behavior with respect to experimentally observed melt stress-optical coefficient ($C_{m})$. \begin{enumerate} \item \textit{J. Phys. Chem. A}, \textbf{107}, 97 (2003) \item \textit{Macromolecules}, \textbf{36}, 2944 (2003) \item P.J. Flory, \textit{Statistical Mechanics of Chain Molecules}, Wiley Interscience, New York (1969) \end{enumerate}