The atomic structure of self-assembled quasi-one-dimensional Gd chains on Si(111) was investigated by low-energy electron diffraction and scanning tunnelling microscopy. Based on comparison between Gd and Ca chains it was shown that this Gd-induced surface reconstruction belonged to the class of honeycomb chain-channel structures. This clearly demonstrated that, besides monovalent and divalent adsorbates, also trivalent adsorbates such as Gd stabilize silicon honeycomb chains. Consequently silicon honeycomb chains emerged as an universal building block in adsorbate-induced silicon surface reconstructions.

Stabilization of Silicon Honeycomb Chains by Trivalent Adsorbates. C.Battaglia, H.Cercellier, C.Monney, M.G.Garnier, P.Aebi: EPL, 2007, 77[3], 36003 (5pp)