Photoconductive Properties and Electronic Structure in 3,5-Disubstituted 2‑(2′-Pyridyl)Pyrroles Coordinated to a Pd(II) Salicylideneiminate Synthon

• Published in: Inorganic chemistry Vol. 60; no. 13; pp. 9287 - 9301
• Main Authors: Ionescu, Andreea, Godbert, Nicolas, Termine, Roberto, La Deda, Massimo, Amati, Mario, Lelj, Francesco, Crispini, Alessandra, Golemme, Attilio, Ghedini, Mauro, Garcia-Orduña, Pilar, Aiello, Iolinda
• Format: Journal Article
• Language: English
• Published: American Chemical Society 05-07-2021
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/acs.inorgchem.0c02991

The synthesis and the electrochemical, photophysical, structural, and photoconductive properties of three new heteroleptic Pd­(II) complexes with various 3′,5′- disubstituted-2-(2′-pyridil) pyrroles H­(N^N) as coordinated ligands are reported. The coordination of the metal center was completed by a functionalized Schiff base H­(O^N) used as an ancillary ligand. The [(N^N)­Pd­(O^N)] complexes showed highly interesting photoconductive properties which have been correlated to their electronic and molecular structures. Theoretical density functional theory (DFT) and time-dependent DFT calculations were performed, and the results were confronted with the organization in crystalline phase, allowing to point out that the photoconductive properties are mainly a consequence of an efficient intramolecular ligand-to-metal charge transfer, combined to the proximity between the central metal and the donor moieties in the solid-state molecular stacks. The reported results confirm that these new Pd­(II) complexes form a novel class of organometallic photoconductors with intrinsic characteristics suitable for molecular semiconductors applications.