MISFIT DISLOCATIONS AT AG MN3O4, CU/MNO AND CU/MN3O4 INTERFACES/

Parallel close-packed plane interfaces between MnO or Mn3O4 and Ag or Cu are studied using high resolution transmission electron microscopy (HRTEM) and atomistic calculations. The study is aimed at determining the network of misfit dislocations at these interfaces. Due to the pro jective nature of HRTEM, an atomistic model incorporating the displace ments associated with the possible misfit-dislocation network appear t o be of great value. The following results are obtained. Ag/Mn3O4: an array of dislocations with line direction [ITO] and alternating Burger s vectors 1/6[11(2) over bar] and 1/3[11(2) over bar], Cu/MnO: a trigo nal network of edge dislocations with Burgers vectors of the 1/6[112] type and line direction [110], Cu/Mn3O4: the Burgers vectors with refe rence to Cu remain of 1/6[112] type, but due to a slight change in lin e direction with respect to [110] obtain some screw character. (C) 199 7 Acta Metallurgica Inc.