L. Ruan et al., SCANNING-TUNNELING-MICROSCOPY STUDY OF S ADSORPTION ON NI(111), Journal of vacuum science & technology. B, Microelectronics and nanometer structures processing, measurement and phenomena, 12(3), 1994, pp. 1772-1775
The chemisorption of sulfur on Ni(111) has been studied by scanning tu
nneling microscopy. At initial adsorption individual S atoms appear as
protrusions 0.3-0.4 angstrom high, forming a local p(2X2) structure n
ear step edges. The p(2X2) structure is found to be a simple S overlay
er structure. After further H2S exposure the surface undergoes a recon
struction to a (5 square-root 3X2) structure, accompanied by a homogen
eous nucleation of small islands resulting from an ejection of Ni atom
s from terraces. The Ni density of 0.80+/-0.03 ML in the (5 square-roo
t 3X2) structure has been determined by measuring the amount of Ni ato
ms used to build the islands.