X-Ray Diffraction (XRD)

X-ray powder diffraction is a technique that uses an X-ray beam to characterize the crystallographic structure of natural and synthetic materials. When crystalline materials are irradiated, a certain portion of the X-ray beams will be scattered by the material’s crystal structure generating a characteristic pattern (diffractogram), unique to each compound. 


The identification procedure is performed by matching the pattern against a database (ICDD), which contains 1 047 661 unique data sets of inorganic and organic substances. 

In addition to pure substances, X-ray diffraction can also be used to characterize mixtures and to determine the ratio of crystalline vs non-crystalline materials in a sample.

Analyzes different types of samples and monitoring phase transitions

Our instrument is equipped with a range of different sample holders that allows us to analyze different types of samples: from powders to fragments, films and microsamples.

Standard powder samples can be measured in reflection and transmission modes. Small samples can be measured mounted on a spinning glass capillary, while larger objects can be placed on the adjustable x-y-z stage.

Additionally, a heating chamber, with a temperature range up to 1200⁰ C, and a climate chamber (up to 300⁰ C) allows to monitor phase transitions under varying relative humidity (RH) and temperature conditions. 

Uses of the X-ray diffraction technique

The technique has been put to a number of uses in the cultural heritage field such as:

  • Analysis of metal corrosion
  • Gemstone decoration on jewellery
  • Pigments on wall paintings
  • Ceramics
  • Opacifiers in glass
  • Salt growth on objects
  • Conservation materials and minerals

In addition to the traditional application to inorganic materials, X-ray diffraction can also be employed to study some organic compounds characterized by partially crystalline structures (e.g. some cellulosic and proteinaceous materials).

Close up of an instrument
X-Y-Z stage with aragonite specimen.
Close up of an instrument
Climate chamber: temperature and relative humidity can be controlled between 10 and 80⁰C, and 0 to 95%, respectively.
Close up of an instrument.
Different sample holders: capillary holder, standard powder sample holder, and a zero-background holder.
Published May 16, 2022 9:56 AM - Last modified May 16, 2022 4:07 PM