Impact of Intermolecular Non-Covalent Interactions in a Cu Pd Discrete Assembly: Conformers' Geometries and Stimuli-Sensitive Luminescence Properties.

A new highly solid-state luminescent phase of a previously reported weakly luminescent Cu Pd dicationic assembly is reported revealing the high geometrical versatility of this moiety that importantly alters its luminescent properties. This very minor new species B is based on a different conformer scaffold than the one encountered in the previously reported B form and, essentially differs from B by displaying shorter Cu -Cu intermetallic distances. DFT calculations allow concluding that the predominance in the solid-state of the weakly luminescent and less stable B phase is due to the extra stability induced by a larger number of intermolecular non-covalent π-CH interactions in its crystalline packing and not by the intrinsic stability of the Cu Pd dicationic moiety.