Band structure and properties of superconducting MgB2 and related compounds (A review)

This paper presents an overview of the current state of the art in research into the electronic structure and properties of a new superconductor, namely, MgB2, and a large number of related compounds by computational methods of the band theory. Consideration is given to the specific features of the surface states of magnesium diboride, the electron and hole doping effects in this compound, and the concentration dependences of the band structure and the properties of Mg1−x Me xB2 and MgB2−y Xy solid solutions and a number of superstructures. The electronic properties of AlB2-like phases, boron, higher borides, a series of ternary layered boron-containing phases, and compounds with structures of the antiperovskite type (MgCNi3 and others) are discussed in terms of their superconducting characteristics. The results obtained in modeling nanotubes and fullerene-like nanoparticles based on MgB2 and related borides are analyzed.