Using helium atom scattering Hulpke and Lüdecke recently observed a giant phonon anomaly for the hydrogen-covered W(110) and Mo(110) surfaces. An explanation which is able to account for this and other experiments is still lacking. Below we present density-functional theory calculations of the atomic and electronic structure of the clean and hydrogen-covered Mo(110) surfaces. For the full adsorbate monolayer the calculations provide evidence for a strong Fermi surface nesting instability. This explains the observed anomalies and resolves the apparent inconsistencies of different experiments.

• Received 25 May 1994

DOI:https://doi.org/10.1103/PhysRevLett.74.1387