Multi-colour circularly polarized luminescence properties of chiral Schiff-base boron difluoride complexes.

A series of chiral Schiff-base boron difluoride complexes was synthesized and their photophysical properties were examined. These complexes showed multi-colour (blue, yellow and red) photoluminescence in solution and in the solid state with good emission quantum yield ( Φ ) depending on the π-systems of the ligands. The chiral complexes exhibited circularly polarized luminescence (CPL) with an absolute luminescence dissymmetry factor ( g lum ) of up to the 1.3 × 10 -3 in solution and 1.9 × 10 -2 in the drop-cast film state. Density functional theory (DFT) and time-dependent (TD) DFT calculations were conducted to further understand the photophysical properties.