Reflectometry Software

Refl1D

for fitting and uncertainty analysis of neutron and X-ray reflectivity data

For Windows: application installer

• Download the “...Windows-x86_64-installer.exe” file from the most recent release at https://github.com/reflectometry/refl1d/releases
• If your browser suggests that this is "unknown" software, follow the prompts to keep it anyway.
• Run the installer: you can optionally add shortcuts to
  • Launch Refl1D webview gui from the Start Menu
  • Launch Refl1D Powershell session (for pip-installing additional libraries, or command-line use)
  • Launch Refl1D webview gui from the Desktop

To upgrade to a newer version, go to "add/remove programs" in Windows settings,  and uninstall the old version before repeating the above steps with a newer version (you can run multiple versions simultaneously without issue)

For MacOS: DMG bundle install

• Choose the correct download for your architecture:
  • Download the "...Darwin-arm64.dmg" if you have a newer M-series mac
  • Download the "...Darwin-x86_64.dmg" if you have an older mac with an Intel processor
• Open the .dmg file and drag the refl1d app to the "/Applications" folder shortcut
• Launch Refl1D webview with "refl1d.app" in the "/Applications/refl1d-<version>" folder
• Launch a Refl1D shell with "refl1d_shell.app", for adding additional pip packages
  • e.g. "pip install molgroups"

Installation from the Python Package Index (pip install)

• Install Python 3 (version 3.9 or greater, such as from  Python.org or Anaconda)
• open a terminal window (plain terminal on mac, Anaconda Prompt on Windows) and issue these commands:
  • pip install refl1d[webview]

Then issuing the command "refl1d" from the command line will start the command-line client, and "refl1d --edit" will start an interactive fitting session.  "pip install --upgrade refl1d" will update to the latest version, any time.

Additional information

See the Refl1D manual for details of the program. Refl1D uses Bumps for fitting and PeriodicTable for scattering length density calculations.

Citing this software: acknowledging Refl1D in publications may be done by making a reference to this site. For example:

The Refl1D program was used for elements of the data analysis[1].
[1] P.A. Kienzle, B.B. Maranville, K.V. O'Donovan, J.F. Ankner, N.F. Berk, C.F. Majkrzak; https://www.nist.gov/ncnr/reflectometry-software 2017-

Reductus

for reduction of raw instrument data to reflectivity data

Reductus is a web application providing support for data reduction of NCNR data.  Driven by the reflred python libraries, reductus supports the common operations required to convert raw X-Ray and neutron reflectivity data to a reflectivity curve in physical units (R vs. Q), performing necessary corrections (background subtractions, scaling etc.)

Data files are accessed directly by URL from the NCNR online data repository and the reduction templates (recipes) can be modified with a graphical editor, and downloaded and reused or shared by email.  Reduced data can be downloaded in columnar text-file form.  No login or password is required to use the application.

Reductus replaces the Reflpak application. 
If you use reductus to reduce your experimental data, please consider including a citation to Journal of Applied Crystallography, Volume 51, Part 5, pages 1500-1506

PeriodicTable

Online SLD Calculator: The online SLD/activation calculator uses the same PeriodicTable package as Refl1D and SasView to compute scattering length density and neutron activation.

Web Reflectivity Calculators

For quick data exploration we provide a browser-based  magnetic reflectivity calculator as well a non-magnetic (unpolarized) reflectivity calculator.  The user-generated SLD profiles can be exported to a heavily-commented Python Refl1D model file to provide an easy way to get started with modeling data in Refl1D.  Please see the article in J. Res. NIST for more details.

Disclaimer

This software was developed at the National Institute of Standards and Technology at the NIST Center for Neutron Research by employees of the Federal Government in the course of their official duties. Pursuant to title 17 section 105* of the United States Code this software is not subject to copyright protection and is in the public domain. NIST does not assume any responsibility whatsoever for the use of this software, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic. The use of certain trade names or commercial products does not imply any endorsement of a particular product, nor does it imply that the named product is necessarily the best product for the stated purpose. We would appreciate acknowledgment if the software is used.

*Subject matter of copyright: United States Government works

Copyright protection under this title is not available for any work of the United States Government, but the United States Government is not precluded from receiving and holding copyrights transferred to it by assignment, bequest, or otherwise.

Acknowledgments

Portions of this work are based upon activities supported by the National Science Foundation under Agreement No. DMR-0412074.

References

Calculating polarized neutron reflectometry

C.F. Majrkzak, K.V. O'Donovan, N.F. Berk (2006); Polarized neutron reflectometry. In Neutron Scattering from Magnetic Materials, T. Chatterji, editor. Elsevier.

Polarization corrections

C.F. Majkrzak (1996); Neutron scattering studies of magnetic thin films and multilayers, Physica B 221, 342-356.

Modelling interfaces with slabs

J.F. Ankner, C.F. Majkrzak (1992); Subsurface profile refinement for neutron specular reflectivity. In S.P.I.E. Conference Proceedings, Vol. 1738. C.F. Majkrzak and J.L. Wood, editors. S.P.I.E., Bellingham, WA.