The projected density of states for a representative coupled and non-coupled structure are presented in Figure . Each structure has 4 Mn atoms and 4 Zn atoms and each has one Mn in an octahedral site. The octahedral Mn states in Figure show a single unoccupied low energy unoccupied state in the spin-up channel as would be expected in a d 4 Mn 3+ cation. The two high energy occupied states in the spin-up channel of the non-coupled structures (Figure ) correspond to the two higher energy filled states in the high-spin d 5 electronic configuration of Mn 2+ .