The observation of dislocations to accommodate the misfit between crystals with different lattice parameters

A thin (800 to 1000 Å) foil', composed of a single crystal layer of PbS and a similar layer of PbSe, was prepared by an evaporation technique. The crystals were in parallel orientation and the interface between them was parallel to (001). The foil was examined in a transmission electron microscope and a square grid of dislocations to take up the misfit between the two lattices was observed. The dislocations were of edge type and their Burgers vectors were 1/2a 〈110〉.