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Updated: Aug 23, 2025
Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles
Published on: June 25, 2018
Nonsymmetric [Pt(C^N*N'^C')] Complexes: Aggregation-Induced Emission in the Solid State and in Nanoparticles Tuned by
Anastasia I Solomatina1, Ekaterina E Galenko1, Daria O Kozina1
1Institute of Chemistry, St. Petersburg State University, Universitetskii av., Sankt-Peterburg, 26, 198504, St. Petersburg, Russia.
Abstract:
Five square-planar [Pt(C^N*N'^C')] complexes (Pt1-Pt5) with novel nonsymmetric tetradentate ligands (L1-L5) were synthesized and characterized. Varying the structure of the metalating aromatic systems result in substantial changes in photophysical properties and intermolecular interaction mode of the complexes in solution and in solid state. The complexes are strongly emissive in tetrahydrofuran solution, with the band maxima ranging from 560 to 690 nm. Three of these complexes (Pt1, Pt2, Pt4) afford nanospecies upon injection of their solution into water, which show aggregation-induced emission (AIE) with a strong red shift of emission bands. In the solid state, crystalline samples of these complexes demonstrate mechanochromism upon grinding with a bathochromic shift of the emission. DFT and TD-DFT computational analysis of monomeric Pt1-Pt5 in solution and model dimeric emitters formed through intermolecular interaction of Pt1, Pt2, Pt4 molecules allowed assignment of observed AIE to the 3 MMLCT excited states of Pt-Pt bonded aggregates of these complexes.
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