How silylene defects at (100) Si surfaces can account for the anomalous features observed via x-ray photoelectron spectroscopy.

A theoretical analysis of the hydrogen-terminated (100) surface of silicon leads to the identification of a new configuration, formed by a silylene center interacting with vicinal silicon dihydrides. This structure may be viewed as a metastable configuration of 2 x 1 (100) (SiH)(2). Silylene can however be stabilized via interaction with water. The paper proposes that some of the anomalous features observed at the hydrogen-terminated or oxidized (100) Si can be attributed to silylene centers datively stabilized by oxo groups or to structures resulting from their decomposition.