Phase relations in the Ga–Mn–N system

The ternary phase diagram of the Ga–Mn–N system was constructed based on phase equilibria calculations and thermodynamic analysis of the relevant phases occurring in the studied system. Furthermore, the pesudobinary GaN–MnNxsections for fixed nitrogen activity were calculated with a view to determine the solubility of Mn in hexagonal GaN. The used thermodynamic model relies on the assessments of the respective binary sub-systems. The only ternary phases considered are the Ga1−xMnxN solid solution, stoichiometric Mn3GaN and the Ga–Mn–N liquid described in terms of binary Redlich–Kister parameters. Ab initio electronic structure calculations of cohesive energies were employed to evaluate the enthalpies of formation of some stoichiometric phases.