Strong Dopant-Dopant Electronic Coupling in Emissive Codoped Two Dimensional Metal Halide Hybrid.

Multimetallic halide hybrids are attractive for the fundamental understanding of interacting excitons. However, realizing halide hybrids that incorporate multiple heterometal centers has been synthetically challenging. This further limits access to gaining physical insight into the electronic coupling mechanism between the constituent metal halide units. Reported herein is an emissive heterometallic halide hybrid, synthesized by codoping (with Mn 2+ , Sb 3+ ) a 2D host (C 6 H 22 N 4 CdCl 6 ) hybrid, that shows strong dopant-dopant interaction. Here, C 6 H 22 N 4 Sb 0.003 Mn 0.128 Cd 0.868 Cl 6 codoped hybrid shows weak green emission (Sb 3+ dopant based) and strong orange emission (Mn 2+ dopant based). The observed dominance of the Mn 2+ dopant emission, arising due to efficient energy transfer between the distant dopants (Sb 3+ → Mn 2+ ), highlights strong dopant-dopant electronic coupling. DFT calculations, supporting the observed dopant-dopant interaction, suggest that the electronic coupling between the dopant units (Mn-Cl; Sb-Cl) is mediated by the 2D networked host structure. This work reports physical insight into the coupling mechanism of interacting excitons in multimetallic halide hybrids synthesized through a codoping strategy.