title: Three-dimensional open-frameworks based on Ln(III) ions and open-/closed-shell PTM ligands: synthesis, structure, luminescence, and magnetic properties.
abstract: A series of isostructural open-framework coordination polymers formulated as [Ln(dmf)(3)(ptmtc)] (Ln = Sm (1), Eu (2), Gd (3), Tb (4), Dy (5); PTMTC = polychlorotriphenylmethyl tricarboxylate) and [Ln(dmf)(2)H(2)O(αH-ptmtc)] (Ln = Sm (1'), Eu (2'), Gd (3'), Tb (4'), Dy (5')) have been obtained by treating Ln(III) ions with PTMTC ligands with a radical (PTMTC(3-)) or a closed-shell character (αH-PTMTC(3-)). X-ray diffraction analyses reveal that these coordination polymers possess 3D architectures that combine large channels and fairly rare lattice complex T connectivity. In addition, these compounds show selective framework dynamic sorption properties. For both classes of ligands, the ability to act as an antenna in Ln sensitization processes has been investigated. No luminescence was observed for compounds 1-5, and 3' because of the PTMTC(3-) ligand and/or Gd(III) ion characteristics. Conversely, photoluminescence measurements show that 1', 2', 4', and 5' emit dark orange, red, green, and dark cyan metal-centered luminescence. The magnetic properties of all of these compounds have been investigated. The nature of the {Ln-radical} exchange interaction in these compounds has been assessed by comparing the behavior of the radical-based coordination polymers 1-5 with those of the compounds with the diamagnetic ligand set. While antiferromagnetic {Sm-radical} interactions are found in 1, ferromagnetic {Ln-radical} interactions propagate in the 3D architectures of 3, 4, and 5 (Ln = Gd, Tb, and Dy, respectively). This procedure also provided access to information on the {Ln-Ln} exchange existing in these magnetic systems.
authors.affiliation: Departament de Nanociència Molecular i Materials Orgànics, Institut de Ciència de Materials de Barcelona, Campus de la UAB, 08193 Bellaterra, Spain.
authors.forename: Angela
authors.initials: A
authors.lastname: Datcu
authors.forename: Nans
authors.initials: N
authors.lastname: Roques
authors.forename: Véronique
authors.initials: V
authors.lastname: Jubera
authors.forename: Inhar
authors.initials: I
authors.lastname: Imaz
authors.forename: Daniel
authors.initials: D
authors.lastname: Maspoch
authors.forename: Jean-Pascal
authors.initials: JP
authors.lastname: Sutter
authors.forename: Concepció
authors.initials: C
authors.lastname: Rovira
authors.forename: Jaume
authors.initials: J
authors.lastname: Veciana
mesh_terms: D018360:Crystallography, X-Ray; D007477:Ions / Q000737:chemistry*; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008024:Ligands; D049449:Luminescence; D008280:Magnetics; D008670:Metals / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D011080:Polychloroterphenyl Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D007477:Ions; D028581:Lanthanoid Series Elements; D008024:Ligands; D008670:Metals; D011080:Polychloroterphenyl Compounds