Small-Angle X-ray and neutron scattering from diamond single crystals

TL;DR

This study uses Small-Angle Scattering to analyze how various defects and treatments in diamond crystals influence nanoscale defect formation, revealing facetted defect structures and their scattering signatures.

Contribution

It provides new insights into the defect structures in diamonds caused by annealing and deformation, linking defect types to scattering patterns.

Findings

Thermal annealing and deformation induce nanosized defects.

Defects are often facetted by specific crystallographic planes.

No clear correlation between nitrogen impurity levels and scattering intensity.

Abstract

Results of Small-Angle Scattering study of diamonds with various types of point and extended defects and different degrees of annealing are presented. It is shown that thermal annealing and/or mechanical deformation cause formation of nanosized planar and threedimensional defects giving rise to Small-Angle Scattering. The defects are often facetted by crystallographic planes 111, 100, 110, 311, 211 common for diamond. The scattering defects likely consist of clusters of intrinsic and impurity-related defects; boundaries of mechanical twins also contribute to the SAS signal. There is no clear correlation between concentration of nitrogen impurity and intensity of the scattering.