The structure and chemical bond characteristics were predicted by means of the density functional theory using the state-of-the-art full-potential linearized augmented plane wave method. The results showed that the present optimized lattice constant, a (4.158Å), parameter, z (0.1981), and bulk modulus, B (170.4GPa), were in good agreement with experimental data. The electron localization function showed that the La-La bond was mainly ionic, the La-B bond was between ionic and covalent while the covalent bond between the nearest neighbor B atoms (B2 and B3) was a little stronger than that between the nearer-neighbor B atoms (B1 and B4).

Structure and Chemical Bond Characteristics of LaB6. Bai, L., Ma, N., Liu, F.: Physica B, 2009, 404[21], 4086-9