organic compounds
In order to clarify relationships between the mesophase behaviour and crystal structures, the X-ray structure determinations of the title compounds, ethyl 4-[4-(4-n-octyloxybenzoyloxy)benzylidene]aminobenzoate, C31H35NO5, and butyl 4-[4-(4-n-octyloxybenzoyloxy)benzylidene]aminobenzoate, C33H39NO5, have been performed. The compounds have different phase sequences, i.e. crystal-smectic A-nematic-isotropic and crystal-smectic C-smectic A-nematic-isotropic for the ethyl and butyl compounds, respectively.