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Scintag XDS 2000 PTS Diffractometer
The phenomenon of diffraction occurs when penetrating radiation,
such as X-rays, enters a crystalline substance and is scattered.
The direction and intensity of the scattered (diffracted) beams
depends on the orientation of the crystal lattice with respect
to the incident beam. Any face of a crystal lattice consists
of parallel rows of atoms separated by a unique distance (d-spacing),
which are capable of diffracting X-rays. In order for a beam
to be 100% diffracted, the distance it travels between rows
of atoms at the angle of incidence must be equal to an integral
multiple of the wavelength of the incident beam. D-spacings
which are greater or lesser than the wavelength of the directed
X-ray beam at the angle of incidence will produce a diffracted
beam of less than 100% intensity.
Our diffractometer utilizes a powdered sample, a goniometer,
and a fixed-position detector to measure the diffraction patterns
of unknowns. The powdered sample provides (theoretically) all
possible orientations of the crystal lattice, the goniometer
provides a variety of angles of incidence, and the detector
measures the intensity of the diffracted beam. The resulting
analysis is described graphically as a set of peaks with % intensity
on the Y-axis and goniometer angle on the X-axis. The exact
angle and intensity of a set of peaks is unique to the crystal
structure being examined. In a multi-component mixture, confusion
can arise when two or more components have a peak in the same,
or nearby, location on the X-axis. It is for sorting out these
mixtures that a good search/match engine or a search method
becomes most important.
The X-Ray diffraction method is most useful for qualitative,
rather than quantitative, analysis (although it can be used
for both). |
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Specifications:
- Identify and, in some cases, quantify phases in solids
and powders and thin films.
- Measure crystal lattice parameters, residual stress, texture,
crystallite size.
- X-ray reflectivity studies.
- Seifert ID3000 computer controlled solid state x-ray generator
with a 2000 W 1x10 mm normal focus Cu target x-ray tube.
- Liquid N2 detector.
- Pentium II 350 MHz PC (Windows NT) running Scintag DMSNT
Diffraction Management System Software v 1.35a
- ICDD Powder Diffraction Database Library
- Crystallographic analysis software package
- Quantitative Analysis Package
- Scan range from 2 - 165 degrees 2Q
- Microstepping stepper motors with a minimum step size
of 0.0003125 degrees.
- Continuous digital two theta scan rates from 0.1 - 120
deg./min.
- Continuously variable goniometer radius from 170 to 300
mm.
Maximum sample size for texture measurement is 2.5 cm long,
1.5 cm wide, and 1.23 cm deep.
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