B(C6F5)3: A lewis acid that brings the light to the solid state

Abstract

The straightforward coordination of the Lewis acid B(C6F5)3 to classical, non-emitting aldehydes results in solid-state photoluminescence. Variation of the electronic properties of the carbonyl moieties lead to the modulation of the solid-state emission colors, covering the entire visible spectrum with quantum yields up to 0.64. Steady-state spectroscopy in combination with X-ray diffraction analysis and DFT calculations confirm that intermolecular interactions between the Lewis adducts are responsible for the observed luminescence. Alteration of the latter interactions induces, moreover, remarkable solid-state phenomena such as piezochromism. The versatility and simplicity of our approach facilitate the future development of solid-state emitting materials. Turn on the light: A straightforward methodology can be used to "switch on" the solid-state fluorescence of non-emitting carbonyl compounds. Subtle electronic changes in the aldehyde moieties lead to a variety of emission colors that cover the entire visible spectrum. The materials also display pressure-dependent luminescent properties (piezochromism).