Synthesis, optical anisotropies, polarisabilities and order parameters of 4-cyanophenyl and 4-isothiocyanatophenyl 4′-butylsulfanylbenzoates with oxygen and sulfur substitution in the ester linkage

The optical anisotropies, polarisabilities, refractive indices and order parameters of 4-cyanophenyl and 4-isothiocyanatophenyl 4′-butylsulfanylbenzoates with oxy- and thin-substitution in all possible combinations in the ester link have been measured and the results are discussed in terms of the position and number of sulfur atoms in the ester linkage. The S-aryl thio- and dithio-benzoates have greater polarisabilities than the corresponding O-aryl esters; the differences between O-aryl and S-aryl thiobenzoates are discussed in terms of the electronegativity and structural changes caused by substitution with sulfur.