Several new mercury acetylide complexes were prepared from substituted phenyl acetylenes. These are of three varieties: i) where normal or branched alkyl chains are attached to the phenyl ring directly. ii) where these chains are attached via an oxygen atom (alkoxy chains), and iii) where the phenyl ring is substituted by two or three alkoxy chains. All the alkoxy derivatives are liquid crystalline. Their mesomorphism has been examined by polarizing microscopy and differential scanning calorimetry.