Mn2CoX (X = P and As) full-Heusler compounds for spintronic applications: Half-metallicity and elastic properties

•Mn2CoP and Mn2CoAs exhibits the ferromagnetic state, and P is more favorable to stabilize the ferromagnetism than As.•Both alloys are thermodynamically, structurally and dynamically stable.•Mn2CoP and Mn2CoAs are half-metallic materials, where the half-metallicity of Mn2CoP is more robust than that of Mn2CoAs.•The magnetism is produced mainly by the 3d-3d interactions.•Materials are mechanically stable, where Mn2CoP is more resistant than Mn2CoAs.