X-ray Structures of Homologous Smectogenic Compounds of 4-Isothiocyanatophenyl 4-( trans -4-Alkylcyclohexyl) Benzoates

The novel crystal structures of the two homologous smectogenic compounds of 4-isothiocyanatophenyl 4-( trans -4-alkylcyclohexyl) benzoates, nTPCHB for n = 8 and n = 12 are described in detail. Both compounds crystallize in the triclinic system with centrosymmetric space group P1 . Typical textures of the nematic and smectic phases have been found from texture studies. Enhancement of smectic layers is involved by molecular dimerization. The crystal to mesophase transition is probably of a displacive nature. The molecular geometry of both compounds is similar, featuring an elongated alkyl chain noteworthy. In both structures, the molecules are packed in a layered arrangement and weak intermolecular interactions are observed. 2D Hirshfeld fingerprint plots indicate that the packing is dominated by H⋯H and C⋯H/H⋯C contacts. Graphic Abstract Ortep representations of nTPCHB for a n = 8 and b n =12. Thermal ellipsoids drawn at 50