title: Lanthanide(III) complexes with 4,5-bis(diphenylphosphinoyl)-1,2,3-triazolate and the use of 1,10-phenanthroline as auxiliary ligand.
abstract: New lanthanide complexes with 4,5-bis(diphenyl)phosphoranyl-1,2,3-triazolate (L(-)), LnL(3).nH(2)O (1-8) and LnL(3)(phen).nH(2)O (9-16) (Ln = La, Ce, Nd, Sm, Eu, Gd, Tb, Er), have been prepared and spectroscopically characterized. The structures of LnL(3).nH(2)O (Ln = La, Ce, Nd, Sm and Gd) were determined by X-ray crystallography. The metal centers exhibit a distorted trigonal dodecahedron coordination environment with two symmetrically O,O-bidentate ligands and one unsymmetrically O,N- ligand attached to the metal; two oxygen atoms from neighboring dimethyl sulfoxide (DMSO) molecules complete the coordination sphere. This unsymmetrical ligand coordination behavior was also identified in solution through (31)P{(1)H} NMR studies. Photoluminescence spectroscopy experiments in CH(2)Cl(2) for both types of complexes containing Eu(III) (6, 14) and Tb(III) (7, 15) exhibit strong characteristic red and green emission bands for Eu(III) and Tb(III), respectively. Furthermore, NdL(3) (phen).5H (2)O (11) displays emission in the near-infrared spectral region ((4)F(3/2) --> (4)F(9/2) at 872 nm and (4)F(3/2) --> (4)F(11/2) at 1073 nm). The complexes containing 1,10-phenantroline exhibit higher quantum yields upon excitation at 267 nm, indicating that this auxiliary ligand promotes the luminescence of the complexes; however, luminescence lifetimes (tau) in this case are shorter than those of the LnL(3).nH(2)O series.
authors.affiliation: Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, D.F. 04510, México.
authors.forename: Marisol
authors.initials: M
authors.lastname: Correa-Ascencio
authors.forename: Elizabeth K
authors.initials: EK
authors.lastname: Galván-Miranda
authors.forename: Fernando
authors.initials: F
authors.lastname: Rascón-Cruz
authors.forename: Omar
authors.initials: O
authors.lastname: Jiménez-Sandoval
authors.forename: Sergio J
authors.initials: SJ
authors.lastname: Jiménez-Sandoval
authors.forename: Raymundo
authors.initials: R
authors.lastname: Cea-Olivares
authors.forename: Vojtech
authors.initials: V
authors.lastname: Jancik
authors.forename: R Alfredo
authors.initials: RA
authors.lastname: Toscano
authors.forename: Verónica
authors.initials: V
authors.lastname: García-Montalvo
mesh_terms: D018360:Crystallography, X-Ray; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D010618:Phenanthrolines / Q000737:chemistry*; D014230:Triazoles / Q000737:chemistry*
chemical_list: C550639:4,5-bis(diphenylphosphinoyl)-1,2,3-triazolate; D028581:Lanthanoid Series Elements; D008024:Ligands; D009942:Organometallic Compounds; D010618:Phenanthrolines; D014230:Triazoles; C025205:1,10-phenanthroline