Two linear hydrogen-bonded liquid crystal homologous series have been isolated in the present investigation and compared. Palmitic acid is chemically bonded with alkyloxy benzoic acids, and alkyl benzoic acids to yield 15 mesogenic complexes. The formation of inter molecular hydrogen bonding is confirmed by Fourier transform infrared spectroscopy (FTIR). Phase polymorphism exhibited by the two linear homologous series is evinced by various textural observations made through polarizing optical microscopic (POM) studies. Differential scanning calorimetry (DSC) studies revealed the transition temperatures and the corresponding enthalpy values exhibited by the individual phases. Phase diagrams has been constructed through POM and DSC data. Thermal equilibrium, thermal stability factor, and order of phase transition data are obtained from DSC study. Influence of oxygen atom attached/detached to the rigid chemical moiety toward the properties of the homologous series is discussed. Light filtering action of the nematogens at different temperatures is also conferred.