a halogenated aromatic monomer - metal complex useful for preparing a polymer for electronic devices such as a light - emitting diode device is described . the aromatic monomer - metal complex is designed to include a linking group that disrupts conjugation , thereby advantageously reducing or preventing electron delocalization between the aromatic monomer fragment and the metal complex fragment . disruption of conjugation is often desirable to preserve the phosphorescent emission properties of the metal complex in a polymer formed from the aromatic monomer - metal complex . the resultant conjugated electroluminescent polymer has precisely controlled metal complexation and electronic properties that are substantially or completely independent of those of the polymer backbone .