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X-Ray Transition Energies Database

NIST Standard Reference Database 128

Last Update to Data Content: September 2005 | Version History & Citation InformationDisclaimer | DOI:

R.D. Deslattes, E.G. Kessler Jr., P. Indelicato,1 L. de Billy,1 E. Lindroth,2 J. Anton,2
J.S. Coursey, D.J. Schwab, J. Chang, R. Sukumar, K. Olsen, and R.A. Dragoset
NIST, Physical Measurement Laboratory
 1 Laboratoire Kastler-Brossell, Ecole Normale Supérieure et Univ. P. et M. Curie, France
2 Stockholm University, Dept. of Atomic Physics, Sweden


This x-ray transition table provides the energies for K transitions connecting the K shell (n = 1) to the shells with principal quantum numbers n = 2 to 4 and L transitions connecting the L1, L2, and L3 shells (n = 2) to the shells with principal quantum numbers n = 3 and 4. The elements covered include Z = 10, neon to Z = 100, fermium. There are two unique features of this database: (1) all experimental values are on a scale consistent with the International System of measurement (the SI) and the numerical values are determined using constants from the Recommended Values of the Fundamental Physical Constants: 1998 [115] and (2) accurate theoretical estimates are included for all transitions. The user will find that for many of the transitions, the experimental and theoretical values are very consistent. It is our hope that the theoretical values will provide a useful estimate for missing or poorly measured experimental values.

This database was published in Reviews of Modern Physics, January 2003 [116] in an article titled "X-ray transition energies: new approach to a comprehensive evaluation." In order to respect page limitations, the numerical values are given only in eV and the sorting is only by element. However, the text that discusses the generation of the theoretical and experimental databases provides more details than are given in the text that accompanies this online database.

  1. Theoretical Transition Energies  
  2. Experimental Transition Energies  
  3. Experimental Edge Energies (Direct, Combined, and Vapor)  
  4. References to the Data
  5. Search the Database

NIST Standard Reference Database 128 | Customer Support | Online: May 2003 | Last update: September 2005

This database was funded [in part] by NIST's Standard Reference Data Program (SRDP), and by NIST's Systems Integration for Manufacturing Applications (SIMA) Program.


Radiation Physics Division

Created July 8, 2009, Updated May 3, 2024