Pressure Control of Cuprophilic Interactions in a Luminescent Mechanochromic Copper Cluster

For the development of applications
based on mechanochromic luminescent materials, a comprehensive study
of the mechanism responsible for the emission changes is required.
We report the study of a mechanochromic copper iodide cluster under
hydrostatic pressure, which allows control of crystal packing via
modification of the intermolecular interactions. In situ single-crystal
powder X-ray diffraction analysis and emission measurements under
pressure permit one to establish a direct correlation between the
molecular structure and luminescence properties and, in particular,
to demonstrate that cuprophilic interactions are responsible for the
stimuli-responsive luminescence properties of such multinuclear coordination
compounds.