The Crystal and Molecular Structure of the Smectogenic Compound 5-Hexyl-2-(4-bromophenyl)-1,3-dioxane

The title compound with the formula C₆H₁₃ C₄O₂H₆ C₆H ₄Br (HBPD) crystallizes in the monoclinic space group C 2/c with lattice parameters a = 28.48 Å, b = 5.71 Å, c = 20.19 Å, β = 97.4° and molecules per unit cell. The structure has been solved by the heavy atom method and refined to a final R value of 0.094. – The HBPD molecules adopt a fully stretched form, both the alkyl and phenyl substituent are in equatorial position with respect to the chair-shaped dioxane ring. The orientation of the phenyl group is an intermediate between the perpendicular and parallel conformation. The molecules show a nearly perfect parallel arrangement in the crystal lattice.