Synthesis of a BaO thin film supported on MgO(001) using a shell-model amorphisation and recrystallisation strategy

An amorphisation and recrystallisation strategy with a shell model representation of ionic polarisability has been used to generate models for thin BaO films supported on an MgO(001) substrate. The resulting BaO thin film includes a complex ?101? dislocation network, the core structures of which have mixed screw-edge and pure edge character. The atomistic core structures of two such dislocations are deconvoluted and presented using graphical techniques. Intermixing of cations across the interfacial plane is observed to be of the order of 1-3%. The amorphisation and recrystallisation strategy improves upon the analogous rigid ion approach in that it enables the ions to retain significant mobility even after recrystallisation enabling additional annealing steps to be performed to allow the ions to rearrange further into low energy configurations. Conversely, the computational cost of such calculations is considerably higher.