The structural, electronic, magnetic, and thermodynamic properties of MnNiCuSb. ErFe4P12 and Ti2CoZ (Z= Sb, Te) have been studied using a full potential linear muffintin- orbital (FP-LMTO) method. The results of the calculations presented in this work were obtained through the use of different approximations LDA, LSDA, and LDA+U. The electronic band structures exhibit that the MnNiCuSb. ErFe4P12 and Ti2CoZ (Z= Sb, Te) alloys have a metallic character. Most of the physical properties of MnNiCuSb. ErFe4P12 and Ti2CoZ (Z= Sb, Te) materials are not available in the literature; this makes the present work as a detailed comparative study for three compounds and opens the path for other future accurate theoretical studies to find the promising substitute for the interesting and more efficient spintronics device in industry.