Polyphenylcyclopentadienyl Ligands as an Effective Light-Harvesting π-Bonded Antenna for Lanthanide +3 Ions.

A new approach to design "antenna-ligands" to enhance the photoluminescence of lanthanide coordination compounds has been developed based on a π-type ligand-the polyphenyl-substituted cyclopentadienyl. The complexes of di-, tri-, and tetraphenyl cyclopentadienyl ligands with Tb and Gd have been synthesized and all the possible structural types from mononuclear to di- and tetranuclear complexes, as well as a coordination polymer were obtained. All types of the complexes have been studied by single-crystal X-ray diffraction and optical spectroscopy.

Lanthanide(III) (Eu, Gd, Tb, Dy) Complexes Derived from 4-(Pyridin-2-yl)methyleneamino-1,2,4-triazole: Crystal Structure, Magnetic Properties, and Photoluminescence.

The reaction of lanthanide(III) nitrates with 4-(pyridin-2-yl)methyleneamino-1,2,4-triazole (L) was studied. The compounds [Ln(NO ) (H O) ]⋅2 L, in which Ln=Eu (1), Gd (2), Tb (3), or Dy (4), obtained in a mixture of MeCN/EtOH have the same structure, as shown by XRD. In the crystals of these compounds, the mononuclear complex units [Ln(NO ) (H O) ] are linked to L molecules through intermolecular hydrogen-bonding interactions to form a 2D polymeric supramolecular architecture.

Bright green-to-yellow emitting Cu(i) complexes based on bis(2-pyridyl)phosphine oxides: synthesis, structure and effective thermally activated-delayed fluorescence.

A family of brightly luminescent dinuclear complexes of [Cu(μ-X)(N^N)] type (X = I or SCN) has been synthesized in 76-90% yields by the reaction of bis(2-pyridyl)phosphine oxides (N^N) with the corresponding Cu(i) salts. The X-ray diffraction study reveals that the CuI core of the [Cu(μ-I)(N^N)] complexes has either a butterfly- or rhomboid-shaped structure, while the eighth-membered [Cu()Cu] ring in the [Cu(SCN)(N^N)] complexes is nearly planar. In the solid state, these compounds exhibit a strong green-to-yellow emission (λ = 536-592 nm) with high PLQYs (up to 63%) and short lifetimes (1.