Syntheses, structures and photophysical properties of a series of Zn–Ln coordination polymers (Ln=Nd, Pr, Sm, Eu, Tb, Dy)

Magnetic and Luminescence Properties of 8-Coordinated Pyridyl Adducts of Samarium(III) Complexes Containing 4,4,4-Trifluoro-1-(naphthalen-2-yl)-1,3-butanedionate

A novel series of polypyridyl adducts, [Sm(ntfa)3(NN)] (2–4), with ntfa = 4,4,4-trifluoro-1-(naphthalen-2-yl)-1,3-butanedionate, NN = 2,2′-bipyridine (bipy), 4,4′-dimethyl-2,2′-bipyridine (4,4′-Me2bipy), and 5,5′-dimethyl-2,2′-bipyridine (5,5′-Me2bipy) were synthesized from the precursor complex [Sm(ntfa)3(MeOH)2] (1) and the corresponding pyridyl ligands. Single X-ray crystallography showed that the complexes displayed 8-coordinated geometry. The solid pyridyl adducts 2–4 exhibited emission of luminescence in the NIR and visible regions with close quantum yields (QY = 0.20–0.25%). The magnetic data of 1–4 showed larger values than those expected for magnetically noncoupled Sm(III) complexes in the 6H5/2 ground state, with no saturation on the applied high magnetic field static at a temperature of 2 K.

Effective Photocatalytic Activity of Mixed Ni/Fe-Base Metal-Organic Framework under a Compact Fluorescent Daylight Lamp

Mixed Ni/Fe-base metal-organic framework (Ni/Fe-MOF) with different molar ratios of Ni2+/Fe3+ have been successfully produced using an appropriate solvothermal router. Physicochemical properties of all samples were characterized using X-ray diffraction (XRD), Raman, field emission scanning electron microscopes (FE-SEM), fourier-transform infrared spectroscopy (FT-IR), N2 adsorption-desorption analysis, X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectra (UV-Vis DRS), and photoluminescence spectra (PL). The photocatalytic degradation performances of the photocatalysts were evaluated in the decomposition of rhodamine B (RhB) under a compact fluorescent daylight lamp. From XRD, IR, XPS, and Raman results, with the presence of mixed ion Fe3+ and Ni2+, MIL-88B (MIL standing for Materials of Institut Lavoisier) crystals based on the mixed metal Fe2NiO cluster were formed, while MIL-53(Fe) was formed with the presence of single ion Fe3+. From UV-Vis DRS results, Ni/Fe-MOF samples exhibited the absorption spectrum up to the visible region, and then they showed the high photocatalytic activity under visible light irradiation. A Ni/Fe-MOF sample with a Ni2+/Fe3+ molar ratio of 0.3 showed the highest photocatalytic degradation capacity of RhB, superior to that of the MIL-53(Fe) sample. The obtained result could be explained as a consequence of the large surface area with large pore volumes and pore size by the Ni2+ incorporating into the MOF’s structure. In addition, a mixed metal Fe/Ni-based framework consisted of mixed-metal cluster Fe2NiO with an electron transfer effect and may enhance the photocatalytic performance.

Tetranuclear Heterometallic {Zn2Eu2} Complexes With 1-Naphthoate Anions: Synthesis, Structure and Photoluminescence Properties

A series of new tetranuclear heterometallic Zn(II) -Eu(III) complexes have been synthesized, that is, (bpy)2 Zn2Eu2 (naph)10 (1), (bpy)2 Zn2Eu2 (naph)8 (NO3)2 (2), and (phen)2 Zn2Eu2 (naph)8 (NO3)2 (3), and other ones, where naph(-) is the 1-naphthoate anion, bpy=2,2'-bipyridyl, and phen=1,10-phenanthroline. The solid-phase complexes consist of large supramolecular ensembles due to stacking interactions between the aromatic ligands. Photoluminescence (PL) measurements were carried out to study PL spectra, lifetimes and quantum yields (QY) of the synthesized complexes at different temperatures. The external QY for the solid phases of complexes under UV excitation was found to exceed 20 %. It has been shown that partial replacement of naphthoate ligands in the coordination environment of Eu(3+) by NO3(-) anions influences the PL properties. To investigate the behavior of these complexes in solvent, we dissolved complex 3 in MeCN, put it on a transparent glass as a substrate, and studied the PL properties at room temperature.

Syntheses, structures, luminescence and magnetic properties of three high-nuclearity neodymium compounds based on mixed sulfonylcalix[4]arene-phosphonate ligands

The solvothermal reactions of p-tert-butylsulfonylcalix[4]arene (H₄BSC4A), phosphonic acid and neodymium chloride have resulted in three novel high-nuclearity neodymium coordination compounds.

A multifunctional lanthanide metal–organic framework supported by Keggin type polyoxometalates

An unusual multifunctional POM@MOF neodymium metal–organic framework with 1D nanotubular channels incorporating Keggin type [SiWV3WVI9O₃₈]³⁻ polyoxometalates was successfully synthesized.

catena-Poly[diimidazolium [bis-(μ-pyridine-2,5-dicarboxyl-ato)bis-[diaqua-praseodymate(III)]]-bis-(μ-pyridine-2,5-dicarboxyl-ato)]

The title compound {(C(3)H(5)N(2))(2)[Pr(2)(C(7)H(3)NO(4))(4)(H(2)O)(4)]}(n), has a chain structure featuring a dimeric unit consisting of two Pr(III) atoms within a dodecahedral environment. Each of the metal cations is coordinated by two N atoms and two O atoms from two pyridine-2,5-dicarboxyl-ate ligands, two O atoms from another two pyridine-2,5-dicarboxyl-ate ligands and two water O atoms. The Pr(III) ions are bridged by two ligands along the c axis, forming the dimeric unit, and these are connected by four ligands along the b axis, forming a chain. N-H⋯O and O-H⋯O hydrogen bonds are found in the structure.

Poly[[octa-aqua-tetra-kis-(μ(3)-pyridine-2,5-dicarboxyl-ato)copper(II)diytterbium(III)] monohydrate]

The asymmetric unit of the title heterometallic polymeric coordination compound, {[CuYb(2)(C(7)H(3)NO(4))(4)(H(2)O)(8)]·H(2)O}(n), contains one Cu(II) cation located on an inversion center, a Yb(III) cation, two pyridine-2,5-dicarboxyl-ate (pda) anions, four coordination water mol-ecules a disordered lattice water molecule, which is half-occupied and is located close to an inversion center. The Cu(II) cation is N,O-chelated by two pda anions in the coordination basal plane and further coordinated by two carboxyl O atoms at the apical positions, with an elongated octa-hedral geometry. The Yb(III) atom is eight-coordinated in a distorted square-anti-prismatic geometry formed by two carboxyl-ate O atoms from two pda anions, and is N,O-chelated by one pda anion and four coordinated water mol-ecules. The pda anions bridge adjacent Yb and Cu cations, forming a three-dimensional polymeric structure. The crystal structure features extensive O-H⋯O hydrogen bonds. π-π stacking is observed between parallel pyridine rings, the centroid-centroid distance being 3.843 (4) Å.