First-principles calculations were made of the electronic band structure by using a full-potential linear muffin-tin orbital method. The influences of the lattice parameter upon the electronic structure were first investigated by using various volumes and c/a ratios. The effects of substitution upon the electronic structure were considered in relationship to the variation of the lattice parameters and electron filling, which was investigated via a Mg pseudo-atom. Variations in the 2-dimensional covalent σ-band and 3-dimensional metal π-band were investigated in detail at several high-symmetry points of the Brillouin zone. The results showed that the variations in the electronic structure were mainly determined by the effect of the c/a ratio.

A First-Principles Study of MgB2 - the Effect of Pressure and Substitution. W.H.Xie, D.S.Xue: Journal of Physics - Condensed Matter, 2001, 13, 11679-87