RSoXS Endstation

About the SST-1 RSoXS Endstation

The Resonant Soft X-ray Scattering (RSoXS) station is the furthest upstream measurement station on the soft branch of the SST-1, SST-2 beamline suite. Initially funded by an award from the NIST Innovations in Measurement Science (IMS) competition in 2018, and operational since 2019, the SST-1 RSoXS station is the newest world-leading facility for RSoXS. The RSoXS station is generally used to measure soft materials and specializes in measurements at the Carbon K X-ray absorption edge, where recent advances have lead to a nearly flat spectrum of X-rays. To learn more about RSoXS and NIST's RSoXS endstation in particular, please explore this wiki, and email the beamline scientist if you have any questions.

Technical Specifications

For more details, see the beamline instrument publication and endstation webpage.

• Beamsize: 250 µm (vertical FWHM) by 350 µm (horizontal FWHM)
• Detector: 4k x 4k Greateyes flange mounted CCD cooled to -80 ºC. Click here for more details.
• Sample Detector Distance: centered at 20 mm - 50 mm (WAXS) and ~500 mm (SAXS - currently out of commission) (use scattering standards to find the precise distance)
• Sample Manipulators: 4 axis (x,y,z, rotation) solid sample holder (1x8 inches) from above, TEM (transmission electron microscopy) holder port compatible with FEI style holders (heating, fluids)
• X-ray Energy range: 70 eV - 2200 eV
• X-ray polarization: linear (0-180 degrees linear), circular (clockwise and counterclockwise)
• sample transmission measurement via beamstop diodes
• drain current from sample stage

Current Scientific Capabilities

RSoXS

• Scattering angles from 2 - 70 degrees  with the WAXS camera - carbon edge size scales from ~5 nm - 80 nm
• (Scattering angles from 0.05 to 4 degrees with the SAXS camera - carbon edge size scales from 40 nm - 3 µm) - currently not available
• A number of standardized scans of common edges available, including the carbon edge at various resolutions (~10 minutes - 0.1 eV, ~5 minutes, 0.2 eV) see the Scans page for details
• Exposure Times as low as 0.002 seconds
• Planned features: Grazing incidence geometry with a new retractable grazing incidence beamstop

NEXAFS

• Multiple Measurement Modes:
  1. Transmission mode using beamstop diodes
  2. Total electron yield (TEY) mode via drain current measurements from the sample holder (for non-insulating samples)
  3. Florescence using wide angle CCD
• Fly scanning enables fast scanning (~1/min per edge) and cyclic NEXAFS measurements (scanning upwards and downwards repeatedly in energy)
• Polarization Specifications:
  1. fixed sample, rotating polarization mode maintains the same beam footprint on the sample, and rotates the beam polarization angle to collect a tilt-angle series
  2. fixed polarization, rotating sample to do a classic tilt angle scan
  3. normal incidence, rotating linear polarization to determine in-plane orientation
• Planned features: Partial Electron Yield (PEY) mode measurements

Literature and resources

• (Non-resonant) Scattering background
  • X-ray Scattering of Soft Matter (textbook): https://link.springer.com/book/10.1007/978-3-540-69856-2
  • NIST neutron scattering school course materials (most principles apply to X-ray scattering): https://www.nist.gov/ncnr/2022-chrns-summer-school-methods-and-application-small-angle-scattering-and-neutron/course
  • Small-angle neutron scattering principles (also applicable to small-angle X-ray scattering): https://www.nist.gov/system/files/documents/2022/10/19/Yimin_Mao_SANS_Principles.pdf
• RSoXS background and general overview
  • RSoXS tutorial: https://doi.org/10.1063/5.0267709
  • Resonant soft X-ray scattering in polymer science: https://doi.org/10.1002/pol.20210414
  • NRSS simulation software: https://doi.org/10.1107/S1600576723002790
  • NIST RSoXS project: https://www.nist.gov/programs-projects/resonant-soft-x-ray-scattering-rsoxs
  • Resonant Soft X-Ray Scattering in Polymer Materials: https://doi.org/10.1146/annurev-matsci-080323-040123
  • NEXAFS spectroscopy: https://link.springer.com/book/10.1007/978-3-662-02853-7
  • Methods in carbon K-edge NEXAFS: Experiment and analysis: https://doi.org/10.1016/j.elspec.2005.11.006
  • Quantitative compositional analysis of organic thin films using transmission NEXAFS spectroscopy in an X-ray microscope: https://doi.org/10.1016/j.elspec.2012.05.002
• Organic photovoltaics
  • Resonant Soft X-ray Scattering for Organic Photovoltaics: https://doi.org/10.1021/acs.jpcb.5c00362
• Polymer chain orientation in polymer-grafted nanoparticles
  • Reconciling Chain Orientation in Polymer-Grafted Nanoparticles between Coarse-Grained Models and Resonant Soft X-ray Scattering: https://doi.org/10.1021/acsnano.4c18022

User guide and resources

Please see SST-1 RSoXS Beamline User Guide for a complete rundown of the process. Some frequently used links are included below for convenience.

• Beam time workflow and Bluesky Guide
• NSLS-II Machine Status Live Operating Status dashboard for the synchrotron (answers: is the beam on?)
• Access your data

Commissioning Notes

Commissioning procedures

Commissioning records: recent and older

Beamline Codebase

All of the bluesky code that runs at the beamline is available here:

• https://github.com/NSLS2/sst-rsoxs-profile-collection (NIST fork: https://github.com/usnistgov/sst-rsoxs-profile-collection)
• https://github.com/NSLS2/sst-rsoxs (NIST fork: https://github.com/usnistgov/sst-rsoxs)
• (currently not used) https://github.com/NSLS-II-SST/rsoxs_workflow (NIST fork: https://github.com/usnistgov/rsoxs_workflow)
• (currently not used) https://github.com/NSLS-II-SST/profile_local_rsoxs
• https://github.com/NSLS-II-SST/workflows-rsoxs (for automatic exporting of data through Prefect)