Synchrotron X-Ray Study of Novel Crystalline-BPhases in Heptyloxybenzylidene-Heptylaniline (7O.7)

This paper reports an x-ray diffraction study of structures and restacking transitions within the $B$ phases of heptyloxybenzylidene-heptylaniline. The system evolves from a hexagonal close-packed structure, through intermediate orthorhombic and monoclinic phases, to a simple hexagonal structure. The monoclinic phase has a temperature-dependent shear which transforms the system from orthorhombic to hexagonal. The latter three phases exhibit a single-$\overrightarrow{\mathrm{q}}$ sinusoidal modulation of the molecular layers.