Surface energy calculation of bcc metals using the analytical equivalent crystal theory method

We have used the newly formulated analytical equivalent crystal theory method which is a modification of the ECT method to calculate the surface energies for three low-index surfaces of bcc alkali metals Li, Na, K, Rb, Cs and the bcc transition metals V, Nb, Ta, Cr, Mo, W and Fe. The data may be used as a starting point for models of surface science phenomena. The accuracy of the surface energies is established from a comparison with other theoretical results and experiment. The surface energy of each (h k l) plane in alkali metals is much lower than that in transition metals. For all bcc metals, the order of the three low-index surface energies is σ110 < σ111 < σ100 in good agreement with the MEAM of Baskes [Phys. Rev. B 46 (1992) 2727] except for Cr and Mo where the ordering obtained in this work is different from that of Baskes. The calculated results show that the surface energy is anisotropic and that the closed-packed plane (1 1 0) is the lowest of the three low-index surfaces.