An investigation was made of the structure, energetics, and effects of stacking faults in MgB2 by means of first-principles density-functional calculations. Two structurally different stacking faults were determined with displacements of R = [0 1/2 0] and [2/3, 1/3 0], and formation energies calculated to be 956 and 932erg/nm2, respectively. Significant expansions were found at both stacking faults. The partial density of states showed that the B atoms in these stacking faults present large reductions in the density of states around the Fermi energy. However, due to their low density, these stacking faults may not cause a significant decrease of the transition temperature of MgB2.

Structures, Energetics and Effects of Stacking Faults in MgB2. Y.Yan, M.M.Al-Jassim: Physical Review B, 2002, 66[5], 052502 (4pp)