Sm. Driver et Dp. Woodruff, Scanning tunnelling microscopy study of the interaction of dimethyl disulphide with Cu(111), SURF SCI, 457(1-2), 2000, pp. 11-23
Scanning tunnelling microscopy has been used to study the interaction of di
methyl disulphide, (CH3S)(2), with Cu(111) at room temperature, which is kn
own to produce adsorbed methanethiolate, CH3S-, by S-S bond scission at the
surface. The results provide clear evidence for the formation of a pseudo-
square surface reconstruction induced by the adsorbate; this reconstruction
can be reconciled with the results of previous structural studies of this
surface by the techniques of X-ray standing wave and surface extended X-ray
absorption fine structure. Two further ordered adsorption phases are obser
ved. One of these, a hexagonal honeycomb phase, is proposed to involve brid
ge and hollow site adsorption on an unreconstructed Cu surface and is metas
table; it is identified as a methanethiolate species previously only studie
d at low temperature by photoelectron spectroscopy and X-ray standing waves
. A third phase of hexagonal symmetry appears to be an alternative endpoint
to the pseudo-square phase, but may be due to higher adsorbate coverages;
the nature of the structure of the underlying copper surface in this case i
s unclear. (C) 2000 Elsevier Science B.V. All rights reserved.