Luminescent Chiral Molecular Glasses by Melt‐Quenching Enantiopure BINAP

Abstract Chiral organic glasses combine unique optical properties with the processing advantages of amorphous solids. Here, melt‐quenching as a strategy for preparing optically active glasses from enantiopure BINAP (2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl), a pivotal ligand in asymmetric catalysis and for luminescent metal complexes is demonstrated. Thermal characterization reveals that only R ‐BINAP and S ‐BINAP, not rac ‐BINAP, form molecular glasses with glass transition temperatures near 100 °C. Pair distribution function analysis and circular dichroism confirm the retention of local structure and homochirality despite the loss of long‐range order. Remarkably, the glassy state has a beneficial influence on the molecular optoelectronic properties relative to the crystalline state, resulting in an increase of the radiative rate constant by ≈30%, attributed to more favourable Franck‐Condon factors. In addition, a highly unusual simultaneous enhancement of circularly polarized luminescence (CPL) by nearly an order of magnitude is observed, achieving dissymmetry factors | g _lum | approaching 10 ⁻² that are competitive with the top‐performing purely organic molecular chiral emitters reported to date. These findings establish melt‐quenched chiral molecular glasses as promising platforms for advanced optoelectronic and photonic materials, combining exceptional chiroptical properties, strong luminescence, and processability without the constraints of crystallinity.