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X-Ray Form Factor, Attenuation, and Scattering Tables
Detailed Tabulation of Atomic Form Factors, Photoelectric Absorption and Scattering Cross Section, and Mass Attenuation Coefficients in the Vicinity of Absorption Edges in the Soft X-Ray (Z = 30-36, Z = 60-89, E = 0.1 keV-10 keV), Addressing Convergence Issues of Earlier Work

C. T. Chantler

School of Physics, University of Melbourne
Parksville, Victoria, 3052 Australia


Reliable knowledge of the complex x-ray form factor [Re(f) and f″] and the photoelectric attenuation coefficient (σPE) is required for crystallography, medical diagnosis, radiation safety, and XAFS studies. Discrepancies between currently used theoretical approaches of 200 % exist for numerous elements from 1 keV to 3 keV x-ray energies. The key discrepancies are due to the smoothing of edge structure, the use of nonrelativistic wave functions, and the lack of appropriate convergence of wave functions. This paper addresses these key discrepancies and derives new theoretical results of substantially higher accuracy in near-edge soft x-ray regions. The high-energy limitations of the current approach are also illustrated. The energy range covered is 0.1 keV to 10 keV. The associated figures and tabulation demonstrate the current comparison with alternate theory and with available experimental data. In general, experimental data are not sufficiently accurate to establish the errors and inadequacies of theory at this level. However, the best experimental data and the observed experimental structure as a function of energy are strong indicators of the validity of the current approach. New developments in experimental measurement hold great promise in making critical comparisons with theory in the near future.

 2001 American Institute of Physics [S0047-2689(00)00604-8].

* This online document reproduces the text and some of the figures from the J. Phys. Chem. Ref. Data 29 (JPCRD 2000) publication. Hence, some of the statements don't take into account the availability of data through the online database. However, the online database has been updated with values from (JPCRD 2000). For a complete comparison of J. Phys. Chem. Ref. Data 24 (JPCRD 1995) with (JPCRD 2000), please refer to the complete journal publication.

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