This study examined the stabilized effect of surface coverage on the coordination properties of methanol on the (1 1 0), (1 0 0), and (1 0 4) surfaces of MgCl2 by periodic DFT. The adsorption energy of different MgCl2 surfaces, which showed the dominance of the (1 1 0) surface over the (1 0 0) and (1 0 4) surfaces, was investigated to prove that methanol could increase surface stability. This study demonstrated that complete coverage of the Mg vacancies on the surface by coordinating methanol was hampered by steric repulsion between the vicinally coordinated donor molecules. Results indicated that the surface of MgCl2 was controlled by choosing an appropriate choice of electron donor. This study provided a sound crystallographic background for Ziegler-Natta catalysts. (C) 2015 Elsevier B.V. All rights reserved.