Ab initio calculations of the energetics of several distortions of the ideal W(001) surface were reported. It was found that this surface was highly unstable against distortions which reduce the surface-atom spacings. Based upon the systematics of the calculated total energy and an analysis of the electronic structure, it was proposed that the instability of the ideal surface could be understood in terms of a local model in which the unreconstructed surface was unstable against distortions which increased the effective coordination numbers of the surface atoms. The results were consistent with a locally liquid-like disordered high-temperature phase.

Bonding and Reconstruction of the W(001) Surface. D.Singh, H.Krakauer: Physical Review B, 1988, 37, 3999-4006