Broad-range emission color tuning in zero-dimensional hybrid metal halides via Sb3+ local structure regulation

Tuning the antimony local structure shifts emission from blue to deep red in halides. • Spin-orbit and electron-phonon coupling jointly influence emission color evolution. • Halide ligands control singlet-to-triplet exciton conversion via the heavy-atom effect. Local structure regulation provides an effective strategy to manipulate the excited-state structures and emission properties of Sb 3+ -activated zero-dimensional (0D) organic-inorganic hybrid metal halides. Herein, we develop a local structure regulation strategy in a series of 0D hybrid metal halides sharing the same C 13 H 22 N + organic cation. By regulating the coordination geometry and halide ligands of Sb 3+ centers, distinct Sb 3+ local coordination structures are constructed, enabling broad emission color tuning from blue at 442 nm to deep red at 710 nm. Photophysical characterizations and first-principles calculations reveal that the emission evolution is governed by the coupled modulation of spin-orbit coupling (SOC) and electron-phonon coupling. In particular, the coordination environment influences the heavy-atom effect and intersystem crossing (ISC) process, thereby altering the relative contributions of singlet-state and triplet-state self-trapped exciton emissions. Furthermore, a transparent emissive hybrid glass with a visible transmittance of up to 88% is obtained by melt-quenching, indicating its potential processability for optoelectronic applications. This work establishes local structure regulation as a practical strategy for controlling exciton dynamics and designing 0D metal halides with widely tunable emission colors. Download: Download high-res image (161KB) Download: Download full-size image Local structure regulation provides an effective route to manipulate the excited-state structures and emission properties of Sb 3+ -activated 0D organic-inorganic hybrid metal halides. By regulating the coordination geometry and halide ligands of Sb 3+ centers, broad emission color tuning from blue to deep red is achieved, while a transparent emissive hybrid glass with high visible-light transmittance demonstrates potential for optoelectronic devices.