Deuteron magnetic resonance experiments on selectively deuterated molecules (TBd-BA) yield the relative orientational orders of the different groups within a molecule in a mesophase. The DMR spectra of methyl, methylene, and aromatic groups are perfectly resolved. The orientational order of the chain segments differs from that of the aromatic core. The chains are not in a rigid state ; however, the observed chain order does not change much by decreasing the temperature from the nematic to the smectic phases. Similar studies on a system with longer chains (BOBd-BA) confirm this point. Experiments where the orientation of the sample in the magnetic field is varied also show that the rotation of the molecule around its long axis is considerably reduced in a metastable low temperature smectic phase