Cu(bis-$\beta$-diketonate) complexes are reported which display columnar liq.-crystal phases with a hexagonal disordered structure (Dhd). The complexes do not have the disk-shape characteristic of most Dhd materials, but produce a disk shape by forming dimers with 90° rotations between nearest neighbors. In the liq.-cryst. state this dimerized nature produces short-range rotational correlations. Three side-chain Cu bis-$\beta$-diketonates with a single Ph substituent are not liq. cryst., and an extension of the mesogenic core is necessary to introduce liq. crystallinity. The simple Ph analogs are monotropic, and the addn. of electron-withdrawing substituents to the Ph moiety results in a stabilization of the mesophase. These substituents produce favorable dipolar interactions which stabilize the mesophase. Consistent with this explanation, electron-donating substituents are not effective at stabilizing the mesophase. Substitution of the complex with thiophene groups rather than phenyls produces stable mesophases with greatly lowered melting and clearing points. This latter result indicates that thiophene substitution provides dispersive forces which destabilize the crystal phase. Thiophene substitution may provide a general method for reducing transition temps. in metallomesogens. [on SciFinder(R)]