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X-Ray Crystallography Facility (XRCF)
X-Ray Crystallography Facility  /  X-Ray Powder Diffraction

X-Ray Powder Diffraction

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Last Updated August 2023

X-ray powder diffraction is an analytical technique that produces a plot of diffracted X-ray intensity vs the angle of diffraction. Both qualitative and quantitative information can be extracted from this diffraction pattern such as the phase composition of the sample, unit cell parameters, crystal size, crystal structure, etc.

The XRCF is equipped with two powder diffractometers located in BI 110. A Rigaku SmartLab and a Panalytical X'Pert Pro (previously operated by the Faber group and moved from Steele).

Rigaku SmartLab

A number of accessories are available for the SmartLab. Including:

  • Air free sample holder
  • Automatic sample changer attachment (six samples)
  • Multipurpose high temperature device capable of temperature up to 1500C
  • Battery Cell attachment
  • Phi attachment base with RxRy attachment head

The use of some of these accessories are complicated and require instruction on their use. If you are interested in using these accessories contact the director.

PANalytical X'Pert Pro

Some features and capabilities of the instrument:

  • Rapid data acquisition requiring about 10 minutes for a routine scan.
  • An automatic sample changer
  • Enclosed high temperature stage for measurements up to 1200C under controlled atmosphere.
  • Capillary sample holder for air-sensitive materials (room temperature evaluation only).
  • Extensive software for data analysis including search-match and Rietveld refinement.

The X-ray powder diffractometers can be run with the assistance of XRCF staff or independently, after training.

Staff Assisted Collection (additional fee may apply)

Any samples that will be collected by XRCF staff should be brought to the lab (clearly labeled) along with a completed XRPD Sample Submission Form.

Independent Users

Caltech users who will be running more than a few samples are encouraged to complete X-ray safety and instrument training to become independent users. Details can be found on the XRPD Training page.

If you are unsure whether instrument training is appropriate contact the director.

Data Access and Processing

  • Data should not be transferred by USB drive from the instrument computer.
  • All data is automatically transferred to the XRCF data server which can be accessed as a Windows network drive, SFTP Server (i.e. WinSCP or FileZilla), or a Caltech Box folder.
  • The facility maintains a number of computers which can be accessed remotely or in BI 128 to process the diffraction data using HighScore.

Anyone interested in access to the XRCF computers, data server, or Caltech Box folder should contact the director.