Chiral Antimony‐Based Halides With Temperature‐Responsive Multimodal Emission

Long‐afterglow luminescent materials are highly sought after for various advanced applications, particularly in the fields of information encoding, anti‐counterfeiting, and temperature sensing. In practical systems, molecular phosphorescence is often quenched at elevated temperatures, making efficient ultralong room‐temperature phosphorescence (RTP) challenging. In this study, chiral Sb‐based halides, ( R / S ‐C 11 H 15 NBr) 2 (NH 4 )SbCl 6 (( R / S )‐C 11 H 14 NBr = ( R / S )‐3‐(4‐Bromophenyl)piperidine), were synthesized as 0D structures in the P 1 space group. Under 345 nm excitation at room temperature, both enantiomers show strong broadband emission centered at 615 nm. They also exhibit circularly polarized luminescence (CPL) with g lum ≈ 3.2 × 10 −4 and reverse thermal quenching with a threshold near 200 K. Notably, under 366 nm excitation, ( S ‐C 11 H 15 NBr) 2 (NH 4 )SbCl 6 exhibits dual cyan‐green RTP bands at 535 and 560 nm, with lifetimes of 104.8 and 111.9 ms, respectively. Temperature‐dependent delayed‐phosphorescence spectra indicate robust resistance to thermal quenching from 80 to 200 K. In contrast, ( R ‐C 11 H 15 NBr) 2 (NH 4 )SbCl 6 shows no detectable RTP. These halides display temperature‐responsive multimodal emission, enabling information encoding, anti‐counterfeiting designs, and temperature‐sensing applications. This pronounced enantiomeric disparity provides a clear model system for chiral afterglow and helps clarify how chirality regulates long‐afterglow mechanisms.