Investigation of the structures of sulfur on Mo(100) by scanning tunneling microscopy

Journal Article · Thu Jul 01 00:00:00 EDT 1993 · Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (United States)

DOI:https://doi.org/10.1116/1.578533· OSTI ID:6238039

Dunphy, J C ^[1]; Sautet, P; Ogletree, D F; Salmeron, M B ^[2]

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1. Center for Advanced Materials, Materials Science Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 and Department of Physics, University of California at Berkeley, Berkeley, California 94720 (United States)
2. Center for Advanced Materials, Materials Science Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)

The structures of the four ordered overlayers of sulfur on the Mo(100) surface were investigated by scanning tunneling microscopy (STM). In order of increasing sulfur coverage, the overlayers have [ital c](2[times]2), [vert bar][sub 1][sup 2] [sub 1][sup [bar 1]][vert bar], [ital c](4[times]2), and [ital p](2[times]1) low energy electron diffraction (LEED) patterns. Only the [ital c](2[times]2) overlayer geometry has been determined from LEED [ital I]([ital V]) analysis. An examination of point and line defects and domain boundaries in STM images provides information beyond that known from LEED on the required symmetries of the ordered overlayers. Several proposed structures were shown to be incompatible with these symmetries and therefore discarded. Only one model of the [ital c](4[times]2) structure was found to be consistent with the symmetry of the STM images. This structure contains sulfur atoms occupying exclusively fourfold hollow sites. Unexpectedly, STM images of the surface with the [ital p](2[times]1) LEED pattern did not have [ital p](2[times]1) symmetry, but consisted of small domains of the [ital c](4[times]2) structure.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6238039
• Journal Information: Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (United States), Vol. 11:4; ISSN 0734-2101
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
MOLYBDENUM
COATINGS
SULFUR
CRYSTAL STRUCTURE
ADSORPTION
ELECTRON DIFFRACTION
LINE DEFECTS
MONOCRYSTALS
POINT DEFECTS
SCANNING ELECTRON MICROSCOPY
COHERENT SCATTERING
CRYSTAL DEFECTS
CRYSTALS
DIFFRACTION
ELECTRON MICROSCOPY
ELEMENTS
METALS
MICROSCOPY
NONMETALS
SCATTERING
SORPTION
TRANSITION ELEMENTS
360602* - Other Materials- Structure & Phase Studies