DISLOCATION STUDIES IN DIAMOND BY X-RAY DIFFRACTION MICROSCOPY

Diamonds of both type I and type IIb were studied by X-ray diffraction microscopy. Long range strain fields are the dominating imperfections in the former, and dislocations appear to be closely related to strain centers. The latter show a much higher density of edge dislocations with Burgers vectors in the (111) planes. These studies corroborate the general view that type I diamond is more perfect but also more strained and type II close to mosaic and less strained. The new findings are discussed in comparison with the birefringence and X-ray diffraction phenomena observed in types I and II diamond.