Luminescent mechanochromic materials based on copper iodide clusters

Overview & Synopsis

Materials exhibiting luminescence stimuli-responsive properties, present potential applications as detection systems. This thesis concerns the study of copper (I) iodide molecular clusters coordinated by phosphine ligands, which exhibit mechanochromic luminescence properties. These compounds are characterized by a change of their emission wavelength in response to mechanical stress. In this thesis, new clusters were synthesized and characterized. The establishment of structureproperties relationships permit to study the mechanisms responsible for their mechanochromic properties. The main characterization techniques used are solid-state NMR, X-ray diffraction, Infrared and Raman spectroscopies. DFT (Density functional theory) calculations were also carried out to rationalize the different results and in particular the optical properties. In addition to the mechanochromic properties, these compounds have the particularity of exhibiting thermochromic luminescence properties. Aggregation-induced emission (AIE) properties were also demonstrated for these clusters. In order to obtain clusters exhibiting multiple emission, ligands having luminescent groups were also studied.