Chiral‐Symmetric Zero‐Dimensional Organic Metal Halides: Temperature‐Independent Circularly Polarized Luminescence and Their Excitonic Dynamics

ABSTRACT Circularly polarized luminescence (CPL) has become a cornerstone in the study of fluorescent materials, offering transformative potential for applications such as autostereoscopic 3D displays, optical information storage and processing, biological encoding and sensing, and anti‐counterfeiting technologies. In this work, two sets of chiral‐symmetric, low‐dimensional organometallic halides were synthesized through a self‐assembly process, resulting in unique 0D molecular architectures. These materials exhibit exceptional optical activity, particularly in chiral luminescence, which can be finely tuned by substituting Cu + with Ag + . A striking feature is their temperature‐dependent behavior: across a range of 80–350 K, the materials display both thermal expansion and negative thermal expansion, accompanied by anomalous luminescence variations driven by changes in excitonic dynamics. Remarkably, temperature‐dependent single‐crystal analyses reveal negligible structural changes, suggesting that the observed luminescent shifts primarily stem from exciton recombination processes. Furthermore, the luminescence dissymmetry factor ( g lum ) remains stable across this temperature range, highlighting its structural origin and affirming the materials’ robustness in thermally variable environments. These findings deepen the understanding of chiral luminescent materials and enhance their potential for advanced optical applications, particularly in designing temperature‐resilient systems for cutting‐edge technologies.