NEXAFS spectroscopy absorption fine structure

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. 

NEXAFS Near-edge X-ray absorption fine strucTure specTroscopy... 

Although the occupied orbitals are of main importance, since they are directly involved in the formation of the chemical bond, the unoccupied states also provide complementary information. In X-ray absorption spectroscopy (XAS), often denoted Near Edge X-ray Absorption Fine Structure (NEXAFS), we excite a core electron to the empty states above the Fermi level [3,4,13]. There is a close connection between XES and XAS where the former gives information on the occupied orbitals while the latter relates to the character and symmetry of the unoccupied levels. Both are governed by the dipole selection rule and the localized character of the core orbitals allows a simple atom-specific projection of the electronic structure the major difference is in the final states. In XAS the empty electronic states are probed... 

Fig. 6.113. Models for (a) 6-mercaptohexadecanol and (b) 22-mercap-todecosanoic acid, adsorbed on gold substrates investigated by near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and X-ray photoelectron spectroscopy. (Reprinted from O. Dannenberger, K. Weiss, H. J. Himmel, B. Jager, M. Buck, and Ch. Woll, Thin Solid Films 307 183, copyright 1997, Fig. 6, with permission from Elsevier Science.)...

The term 1 or h indicates low or high coverage of adsorbed ethene, as inferred from ethene exposures.h TPD, temperature-programmed desorption LITD, laser-induced thermal desorption 1 FT-MS, Fourier-transform mass spectrometry SIMS, secondary-ion mass spectrometry MS, mass spectrometry T-NEXAFS, transient near-edge X-ray absorption fine structure spectroscopy RAIRS, reflection-absorption infrared spectroscopy. d Data for perdeut-erio species.1 Estimated value. 

Recently, carbon (Is) near-edge X-ray absorption fine structure (C (Is) NEXAFS) spectroscopy using synchrotron radiation has been applied to carbon (C) speciation and to investigate source apportionment of combustion derived particulate matter, as well as to predict a possible decay path for carboxylic groups in soot by photo-... 

S., and Jacobsen, C. (2005). Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy for mapping nano-scale distribution of organic carbon forms in soil Application to black carbon particles. Global Biogeochem. Cycles 19, GB1013. 

NEXAFS NIBIB Near-edge X-ray Absorption Fine Structure (Spectroscopy) National Institute of Biomedical Imaging and Bioengineering... 

NBTC NC ND Nd YAG ndc NDR NEST NEXAFS Nanobiotechnology Center (Cornell University) nanocrystal nanodiamond neodymium-doped yttrium aluminium garnet (laser) 2,6-naphthalenedicarboxylate 2-nitro-jV-methyl-4-diazonium-formaldehyde resin New and Emerging Science and Technology near-edge x-ray absorption fine structure (spectroscopy)... 

NEXAFS — Near-edge extended X-ray absorption fine structure (spectroscopy), evaluation of the X-ray absorption spectrum around and slightly below the absorption edge, for details see - EXAFS. 

This paper will discuss the use of Near-Edge X-ray Absorption Fine Structure (NEXAFS) Spectroscopy to study the unoccupied n molecular orbital (MO) structures of polymers and polymer-metal interfaces. A collection of systematic NEXAFS and EELS studies of simple organic compounds by J. Stohr and others (1-10) has led to recent advances in the understanding and interpretation of this technique. It s application to complicated polymers and polymer-metal interactions has only begun, but NEXAFS spectroscopy promises to be an important complement to other photoelectron spectroscopies. 

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