title: Self-assembly of highly luminescent lanthanide complexes promoted by pyridine-tetrazolate ligands.
abstract: Two tridentate pyridine-tetrazolate ligands (H(2)pytz and H(2)pytzc), analogues of the well-known dipicolinate (H(2)dpa) ligand, have been synthesized in a straightforward manner and used for lanthanide(III) coordination. The structures of the resulting tris-ligand complexes were determined in solution ((1)H-NMR), where they remain undissociated, as well as in the solid state (X-ray diffraction). The solubility of these anionic complexes can be easily tuned by changing the countercation. The bis-tetrazolate-pyridine ligand H(2)pytz sensitizes very efficiently both the visible and near-IR emission of the lanthanides, with unusually high luminescence quantum yields in solid state (61% and 65% for Eu and Tb, respectively, and 0.21% for Nd) and in water (63% for Tb and 18% for Eu). Furthermore, the absorption window of the complexes is significantly extended towards the visible region up to 330 nm. The results show that the bis-tetrazolate-pyridine ligand provides a very attractive alternative to the classic dipicolinate ligand.
authors: CEA Grenoble, INAC, SCIB, Laboratoire de Reconnaissance Ionique et Chimie de Coordination, UMR-E 3 CEA-UJF, 38054, Grenoble Cedex 9, France.
authors: Eugen S
authors: ES
authors: Andreiadis
authors: Daniel
authors: D
authors: Imbert
authors: Jacques
authors: J
authors: Pécaut
authors: Renaud
authors: R
authors: Demadrille
authors: Marinella
authors: M
authors: Mazzanti
mesh_terms: D000042:Absorption; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008024:Ligands; D049408:Luminescent Agents / Q000138:chemical synthesis / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D012996:Solutions; D013777:Tetrazoles / Q000737:chemistry*
chemical_list: D028581:Lanthanoid Series Elements; D008024:Ligands; D049408:Luminescent Agents; D009942:Organometallic Compounds; D011725:Pyridines; D012996:Solutions; D013777:Tetrazoles; C023666:pyridine