ALS beamline 12.2.2

Synchrotron X-ray diffraction under non-ambient conditions

Beamline 12.2.2 at the Advanced Light Source is a synchrotron X-ray diffraction beamline for samples at non ambient conditions of pressure, temperature and atmospheric conditions.

The beamline photon energy range is 6-35keV with a minimal x-ray spot size of 5x5 um.

The beamline offers mainly three areas of expertise:

- High-pressure X-ray powder diffraction through diamond anvil cells in axial or radial diffraction. Both geometries can be combined with double-sided laser heating.

- Ambient pressure X-ray powder diffraction at temperatures up to ~ 1000 C and simultaneous controlled atmosphere.

- High-pressure X-ray single crystal diffraction allowing for large DAC's (BX90, symmetric cells). This capability is currently available in a single axis configuration. A 4-circle goniometer is being commissioned on endstation 1.

Image from Physics World

Using in situ synchrotron x-ray diffraction and Raman spectroscopy in concert with first principles calculations we demonstrate the synthesis of stable Xe(Fe,Fe/Ni)3 and XeNi3 compounds at thermodynamic conditions representative of Earth’s core. Surprisingly, in the case of both the Xe-Fe and Xe-Ni systems Fe and Ni become highly electronegative and can act as oxidants. The results indicate the changing chemical properties of elements under extreme conditions by documenting that electropositive at ambient pressure elements could gain electrons and form anions.

Beamline acknowledgement policy:


  • Any publication connected to work on beamline 12.2.2 or the high-pressure lab (6-2241) must be acknowledged in the following manner:

Beamline 12.2.2 at the Advanced Light Source is a DOE Office of Science User Facility under contract no. DE-AC02-05CH11231.

  • Any publication benefiting from the use of the 12.2.2 laser mill in the preparation lab 6-2241 must be acknowledged in the following manner:

This research was partially supported by COMPRES, the Consortium for Materials Properties Research in Earth Sciences under NSF Cooperative Agreement EAR 1606856


Please note that failure to include these acknowledgment may jeopardize future access to beamline 12.2.2 and/or its support facilities.

Financial Support


U.S. Department of Energy - The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

COMPRES - Beamline 12.2.2 is partially supported by COMPRES, the Consortium for Materials Properties Research in Earth Sciences under NSF Cooperative Agreement EAR 1606856"