The Metal-Metal-to-Ligand Charge Transfer Excited State and Supramolecular Polymerization of Luminescent Pincer Pd II -Isocyanide Complexes

Pincer Pd -isocyanide complexes are described that display intermolecular interactions and emissive MMLCT excited states in aggregation state(s) at room temperature. The intermolecular Pd -Pd and ligand-ligand interactions drive these complexes to undergo supramolecular polymerization in a living manner. Comprehensive spectroscopic studies reveal a pathway with a kinetic trap that can be modulated by changing the counteranion and metal atom. The Pd supramolecular assemblies comprise two different aggregation forms with only one to be emissive. DFT/TDDFT calculations lend support to the MMLCT absorption and emission of these pincer Pd -isocyanide aggregates.