X-RAY NEAR EDGE ABSORPTION

Figure Bl.22.10. Carbon K-edge near-edge x-ray absorption (NEXAFS) speetra as a fiinotion of photon ineidenee angle from a submonolayer of vinyl moieties adsorbed on Ni(lOO) (prepared by dosing 0.2 1 of ethylene on that surfaee at 180 K). Several eleetronie transitions are identified in these speetra, to both the pi (284 and 286 eV) and the sigma (>292 eV) imoeeupied levels of the moleeule. The relative variations in the intensities of those peaks with ineidenee angle ean be easily eonverted into adsorption geometry data the vinyl plane was found in this ease to be at a tilt angle of about 65° from the surfaee [71], Similar geometrieal detenninations using NEXAFS have been earried out for a number of simple adsorbate systems over the past few deeades.

Zaera F, Fischer D A, Shen S and Gland J L 1998 Fluorescence yield near-edge X-ray absorption spectroscopy under atmospheric conditions CO and FI2 coadsorption on Ni(IOO) at pressures between 10 and 0.1 Torr Surf. Sc/. 194 205-16... [Pg.1798]

Zaera F, Fischer D A, Carr R G and Gland J L 1988 Determination of chemisorption geometries for complex molecules by using near-edge X-ray absorption fine structure ethylene on Ni(IOO) J. Chem. Rhys. 89 5335-41... [Pg.1798]

Fischer D, Marti A and Hahner G 1997 Orientation and order in microcontact-printed, seif-assembied monoiayers of aikanethiois on goid investigated with near edge x-ray absorption fine structure spectroscopy J. Vac. Sc/. Technol. A 15 (4) 2173-80... [Pg.2638]

Near edge x-ray absorption fine stmcture spectroscopy (nexafs) and x-ray photoelectron spectroscopy (xps) have been used to study SAMs of OTS, octadecyltrimethoxysilane (OTMS), CH2(CH2) ySi(OCH2)3, and (17-aminoheptadecyl)-trimethoxysilane (AHTMS), H2N(CH2) ySi(OCH3)3 (149). A number of important observations have been reported. First, the chains in OTS SAMs are practicaUy perpendicular to the substrate surface (tilt angle... [Pg.537]

Surface Extended X-Ray Absorption Fine Structure and Near Edge X-Ray Absorption Fine Structure (SEXAFS/NEXAFS)... [Pg.18]

EXAFS is part of the field of X-ray absorption spectroscopy (XAS), in which a number of acronyms abound. An X-ray absorption spectrum contains EXAFS data as well as the X-ray absorption near-edge structure, XANES (alternatively called the near-edge X-ray absorption fine structure, NEXAFS). The combination of XANES (NEXAFS) and EXAFS is commonly referred to as X-ray absorption fine structure, or XAFS. In applications of EXAFS to surface science, the acronym SEXAFS, for surface-EXAFS, is used. The principles and analysis of EXAFS and SEXAFS are the same. See the article following this one for a discussion of SEXAFS and NEXAFS. [Pg.215]

NEXAFS Near-Edge X-Ray Absorption Fine Structure... [Pg.766]

The deposition conditions should be optimized to obtain approximately equal amounts of matrix and spreader-bar molecules on the surface [18,21]. Analysis of monolayers by near-edge X-ray absorption fine-structure spectroscopy. [Pg.322]

Outka DA, Stohr J, Jark W, Stevens P, Solomon J, Madix R. 1987. Orientation and bond length of molecular oxygen on Ag(llO) and Pt(lll) A near-edge X-ray-absorption fine-structure study. Phys Rev B 35 4119-4122. [Pg.311]

NEXAFS Near-edge X-ray absorption fine structure (see XANES)... [Pg.757]

Kinetics of Ethylidyne Formation on Platinum(lll) Using Near-Edge X-ray Absorption Fine Structure... [Pg.131]

Nd YAG Q-switched laser, in fine art examination/ conservation, 11 413 N-donating ligands, complexation with uranium, 25 434-436 Near-edge X-ray absorption fine structure (NEXAFS), 24 72... [Pg.614]

Near-edge X-ray absorption spectroscopy and bonding, 34 223-235 continuum spectral features, 34 234-235 edge widths, 34 233-234 energy shifts and coordination charge, 34 228... [Pg.152]

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