Investigation of the interactions between ferroelastic domain walls and of the structural transition in lead phosphate observed by electron microscopy. II. Interpretation of the interactions between ferroelastic domain walls

In Part I experimental results are presented showing the importance of elastic strains around the intersections of domain walls in the monoclinic phase of lead phosphate. In the present paper the different situations are described in terms of dislocation theory. Infinite domain walls do not generate any deformation in the two contiguous lattices. On the other hand the mechanical incompatibilities of the lattices around domain wall intersections produce long range stresses due to rotational defects located on the junctions. Calculation of the stresses created by the wall junctions permits to explain the different experimental results.