Phase (matter)

Supercell

Thunderstorm

Materials science

Electronic band structure

Density functional theory

Crystal structure

Electronic structure

Computer science

Physics

Organic chemistry

Cluster (spacecraft)

Doping

Superconductivity

Chemical bond

Condensed matter physics

Computational chemistry

Crystallography

Chemistry

Programming language

Meteorology

Covalent bond

Bond length

Density of states

Applied Mechanics and Materials

First-principle calculations were performed for the study of the superconductor MgB 2 and AlB 2 . The doping effect of compound Mg 1-x Al x B 2 was analyzed by supercell method. Band structure, electronic bands structure, total and partial densities of states were calculated and analyzed in detail. Covalent bond effects (CBC) appeared in the electronic bands structure when doping Al to MgB 2 . It is found that this CBC effects on Mg 1-x Al x B 2 samples have prominent relations to superconductivity. The study of the density of state indicates that the superconductivity decreases with the increase of compound Al. In particular, there exists the transition of superconductor to non-superconductor with the change of x. The theoretical predictions agreed well with experimental measurements.

Covalent Bond Cluster Effects and Phase Transitions in Superconductor Mg&lt;sub&gt;1-x&lt;/sub&gt;Al&lt;sub&gt;x&lt;/sub&gt;B&lt;sub&gt;2&lt;/sub&gt; Compounds

Covalent Bond Cluster Effects and Phase Transitions in Superconductor Mg&lt;sub&gt;1-x&lt;/sub&gt;Al&lt;sub&gt;x&lt;/sub&gt;B&lt;sub&gt;2&lt;/sub&gt; Compounds

Covalent Bond Cluster Effects and Phase Transitions in Superconductor Mg<sub>1-x</sub>Al<sub>x</sub>B<sub>2</sub> Compounds