Effects of structural change on half-metallicity of CoMnZ (Z=P, As, Sb): A first-principle study

► C1b structure is more energy favored in CoMnZ (Z=P, As, Sb) compounds. ► C1b CoMnZ (Z=P, As, Sb) are all half-metals at equilibrium lattice constant. ► Half-metallicity in CoMnZ (Z=P, As, Sb) is retained in considerable volume distortion. ► Half-metallicity in CoMnP and CoMnAs is more robust than CoMnSb under tetragonal distortion.