The change in backbone conformation from prolate to oblate upon going from the re-entrant nematic to the smectic Ad phase is studied in a comb-shaped polyacrylate by measuring the mosaicity of the sample in the smectic phase with X-ray scattering. In combination with the possibility of aligning the director in both nematic phases, the results indicate that the conformational change takes place in the re-entrant nematic phase upon approaching the smectic Ad phase.

Liq. Cryst.

Bouwman, W. G, & de Jeu, W. H. (1994). X-ray study of the backbone conformation of a comp-shaped polyacrylate with nematic to smectic A phase transitions. Liq. Cryst., 16, 853–856.