X-Ray Diffraction
The Bruker AXS X-Ray Diffractometer
Dr. Hinthorne Explains How the X-Ray
Diffractometer Works "The X-Ray Diffractometer works by generating
x-rays in this x-ray tube on the left side and collimating them into
a parallel beam to impinge on the sample in the center of the
chamber. We have a camera with a laser attachment for vertical
adjustment and horizontal positioning of our sample in the center of
the x-ray beam. The diffracted x-rays, that is, the ones that
are reflected at particular angles off the crystalline substance we
use for a sample, are detected by the moving arm and detector on the
right-hand side of the unit and displayed on the computer screen as
what's called an x-ray diffraction pattern. Data processing on
the diffraction pattern will extract the peaks from the background
and compare them to a database of peaks for identification of the
sample material." -Dr. Hinthorne
Student Researcher Thomas Mion Loads an Unknown
Sample
The diffraction pattern is processed through EVA, a data
evaluation program. As shown on the right-hand computer
screen, the program searches through a database of all known
minerals and inorganic compounds to find the matching diffraction
pattern and thus identify the sample material. X-ray
diffraction may also be used to characterize the atomic-scale
structure of an already identified crystalline substance.
X-Ray Diffraction Sample Request Form
The computer screen on the left depicts the diffraction pattern from
the sample that was loaded by Thomas. The height of the peak
represents the relative intensity of the diffracted x-rays. The
position of the peak on the horizontal scale represents the angle of the x-ray
diffracting from the sample material. The combination of these
intensities and angles
are what make up a diffraction pattern, unique to a given material.