Supercooled Liquid Phases of Luminescent Zero Dimensional Metal Halide Hybrids

Chemical design of metal halide hybrids (MHHs) with suppressed melting point (Tm) allows access to glassy phases from their liquid-melts. Thermal phase change (crystal–melt–glass) properties of glassy MHHs (with glass transition temperature Tg > room temperature) have been exploited for device applications. However, room temperature stable supercooled liquid (SCL) MHHs (with Tg 2+,Cd2+; Mn2+,Zn2+; Benzyltributylammonium) with low Tg (15–16 °C), low Tm (90–100 °C), green luminescence, and high optical transparency. Structural, optical, thermal, and computational analyses highlight chemical design principles and support dopant (Mn2+) based luminescence. Rheological measurements confirm the SCL phase that shows thermal hysteresis and estimate relaxation time scales. This work provides a new material platform showcasing enhanced melt-processability for fabrication of moldable devices, unravelling chemical makeup–property correlation and expanding the material phase types of MHHs.