Structure of cubic phases of BABH-n homologues

Abstract

The cubic (Cub) phase structure of 1,2-bis(4-n-alkoxybenzoyl)hydrazines (BABH-n, where n is the number of carbon atoms in the alkoxy group) was examined. The X-ray diffraction results revealed that, similarly to the n=8 homologue, all Cub phases for n=9-12 are of Ia3d type, with a good linear relationship of the lattice constant (a) with n. The value of (1/a)(da/dT) was positive for n=9-12 except the cooling process of n=12. The infrared spectral studies showed a slight different tendency for the hydrogen bonding dissociation of N-H groups between the homologues with n=9 and 10, and higher. The difference may be explained in terms of the average molecular shape dependence on n.