A systematic study of the liq.-cryst. properties of 30 metal bis($\beta$-diketonate) complexes (M = Cu, VO, Pd) that exhibit discotic mesophases is reported. This study has detd. that the ability of the metal center to influence the mesophase stability depends upon the d. of side chains. In the 10-side-chain complexes I, all of the materials were liq. cryst. In this series the M = VO analogs have lower melting and clearing points than those with M = Cu and M = Pd. For the 12-side-chain series II the opposite is true, and the M = VO materials have substantially higher clearing points. The differences between series I and II arise from the enhanced core-core interactions that accompany the increased side-chain d. The side-chain-induced organization assists the expression of the metal center's character in detg. the stability and nature of the mesophase. The fact that the transition temps. of the M = Cu and M = Pd compds. differ more in series II than in series I is also a manifestation of this greater organization. The influence of the metal centers is discussed in the context of intermol. dative assocns. and for some phases of the M = VO materials these interactions produce polymeric (-V:O-V:O-)n structures. [on SciFinder(R)]