iDPC-STEM measurements of the positions of the oxygen anions and their relationship to the perspective. This concealment is attributed to the alternating pattern of octahedral tilting and the overlapping arrangement of oxygen atoms parallel to the b-axis. This stands in contrast to observations from the [100] projection, where cooperative tilting of BO6 octahedra within the B6TFMO structure is distinctly evident in both DFT models (Figure (h)) and STEM-iDPC images (Figure (f), (g), (i)). Through an examination of oxygen positions and a comparative analysis with existing literature , , it becomes apparent that a tilt mode akin to the irreproducible representation (irrep) 𝑋 3 + (SI Figure ) is present. This mode accounts for the outof-plane (parallel to c) anti-phase tilting of octahedra with respect to each other in the ab-plane.