Material Characterization by PDF and RDF Analysis

Application Note B-XRD1107


Pair Distribution Function (PDF) and Radial Distribution Function (RDF) analyses can derive atomic distances and atomic coordinates from an X-ray diffuse scattering pattern regardless of the crystallinity of the materials. Therefore, it is possible to perform the analysis for amorphous materials and nanomaterials that present broad peaks called halos.  

Measurements and results

The X-ray scattering pattern from amorphous materials like amorphous carbon has much broader peaks compared to those of crystalline materials (Figure 1). These peaks are caused by the X-ray diffuse scattering corresponding to the various C-C distances. Hence, real space information, such as atomic distances and atomic coordination numbers, can be obtained from the inverse Fourier transformation of the X-ray diffuse scattering. Figure 2 shows an RDF profile, where the horizontal axis is the atomic distance and the vertical axis is the atomic coordination number. Peak positions and integrated intensities correspond to atomic distances and the atomic coordination number of carbon in the structure shown in Figure 3.

B-XRD1107 Figure 1 X-ray scattering patternFigure 1: X-ray scattering pattern 

B-XRD1107 Figure 2 RDF profile from amorphous carbon Figure 2: RDF profile from amorphous carbon 

B-XRD1107 Figure 3 Crystal structure of carbon Figure 3: Crystal structure of carbon 

Contact Us

Whether you're interested in getting a quote, want a demo, need technical support, or simply have a question, we're here to help.