green emitters, and thus it is critical to provide a structural understanding of the
photophysical process. Herein, we propose that a sufficiently long Mn–Mn distance in 0D
metal halides enables all Mn2+ centers to emit spontaneously, thereby leading to near-unity
photoluminescence quantum yield. Taking lead-free (C10H16N) 2Zn1–x Mn x Br4 (x= 0–1)
solid solution as an example, the Zn/Mn alloying inhibits the concentration quenching that is …