Citation: Spanopoulos, Ioannis; Ke, Weijun; Stoumpos, Constantinos C.; Schueller, Emily C.; Kontsevoi, Oleg Y.; Seshadri, Ram; Kanatzidis, Mercouri G. (2018). Unraveling the Chemical Nature of the 3D "Hollow" Hybrid Halide Perovskites.. Journal of the American Chemical Society, 140, pp. 5728-5742.