Fig. 4. An example of how to obtain the halide-based Bloch waves at one of the high-symmetry k points of the double-perovskite lattice. The SALC we place at the B site (the “input SALC” highlighted in red, in this example T1u) is propagated along the unit-cell axes using the translational symmetry of the k point (in this example L). Here, translational symmetry generates a SALC at the B′ site that exhibits A1g symmetry (the “output SALC”, highlighted in pink). Yellow and white lobes represent positive and negative phases, respectively.
