The adsorption of atomic hydrogen in the high coverage regime was investigated. It was found that the surface under these conditions underwent a reconstruction into the fairly rare pgg or p4g symmetry. The reconstruction was found to coincide with a new high-resolution electron energy loss spectroscopy energy loss feature, besides the one present at the low coverage which was interpreted as hydrogen in a hollow site. The new loss feature was interpreted as hydrogen positioned in a bridge bonded site. Two models with the correct symmetry were considered.

The p4g or pgg Reconstruction on Cu(100). I.Chorkendorff, P.B.Rasmussen: Journal of Physics - Condensed Matter, 1991, 3[S], 107-10