a new series of mononuclear ortho-platinated complexes based on the combination of rod-like phenylpyridine,which contains a 4'-alkoxy substituted biphenyl-4-carbonitrile unit at 5-posittion in the pyridine ring and alkoxy chain at the 4-position in the phenyl ring,and the 1,3-diketone with flexible alkyl chains were synthesized.The metallomesogenic properties of complexes were characterized by polarized optical microscopy (POM),differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WXRD).These complexes are intensely phosphorescent at room temperature in solution and solid films.Moreover,the complexes exhibit lamellar smectic metallomesogens or two-dimensional crystalline order at lower temperature.The aligned films based on these luminescent mesophase on rubbed polyimide show higher anisotropy in the absorption and photoluminescence at room temperature.Maximal dichroic ratio at 360 nm achieved up to 6.0 for the aligned film of complex a and maximal emission polarization ratio of 13.4 at 513 nm was obtained for the aligned film of complex c.