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X-Ray Fluorescence Downloads

This page is a repository for important x-ray fluorescence (XRF) files and documents associated with NIST XRF activities.  The historic codes are good examples of the type of information kept here. These files are offered for free download and unrestricted distribution. There is no support available for the Fortran codes.

Historic Codes

NRLXRF and NBSGSC were pioneering works in the computerization of fundamental parameter and influence coefficient methods. Users must compile the codes for their platforms, which may involve some modification of the codes. One known problem is that NRLXRF uses ENCODE/DECODE commands that are not supported by all compilers.

Fundamental Parameters Database

A few years ago, W.T. Elam spent some sabbatical time at NIST. One of the accomplishments was a new compilation of fundamental parameters described in W.T. Elam, B.D. Ravel and J.R. Sieber, Radiation Physics and Chemistry, 63 (2), 121 (2002). "A new atomic database for X-ray spectroscopic calculations". The authors have not tested this compilation. However, it has been requested by dozens of researchers and is already incorporated into several experimental FP programs. Download the Elam FP compilation here. [WinZip File]

NIST has additional fundamental parameter information available through the Physics Laboratory Physical Reference Data web site:

Created November 13, 2009, Updated September 21, 2016