Utilizing nitronyl nitroxide biradical NITPhPyObis [5-(3-pyridinyloxy)-1,3-bis­(1′-oxyl-3′-oxido-4′,4′,5′,5′-tetramethyl-4,5-hydro-1H-imidazol-2-yl)-benzene], a family of isomorphic 2p–3d–4f complexes [Ln2­Cu2­(hfac)10­(NITPhPyObis)2] (hfac = hexafluoroacetylacetonate; LnIII = Gd (1), Dy (2), and Ho (3)) were successfully produced. The biradical NITPhPyObis of 1-3 is ligated to the LnIII ion through its two NIT moieties in a chelating mode while the N donor of pyridine and one NO group of this biradical bind one CuII ion, respectively, yielding a tetranuclear heterometal cyclic cluster. Magnetic studies indicate that ferromagnetic exchanges dominate in these 2p–3d–4f clusters which origin from the Ln-NO and axial NO-Cu couplings. Spin dynamics studies show that the χ′ and χ″ signals of Cu–Dy derivative exhibit both temperature dependence and frequency dependence in 0 Oe dc field, demonstrating slow magnetic relaxation behavior. The obtained energy barrier for demagnetization is U eff = 15.8 K. The value almost is three times larger than that of the related Dy cluster [Dy4(hfac)12(NITPhPyObis)2] (U eff = 5.2 K) which indicates the magnetization relaxation rate of the birad–Ln cluster is reduced through introducing Cu­(II) ion.

The self-assembly of nitronyl nitroxide radical NIT-4trz-2Py (NIT-4trz-2Py = 2-(4-(1-triazole)-2-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) with Ln­(hfac)3·2H2O (hfac = hexafluoroacetylacetonate) has successfully afforded two 1D chains [Ln­(hfac)3NIT-4trz-2Py] (LnIII = TbIII 1, DyIII 2) and four discrete trinuclear species [Ln3(hfac)9(NIT-4trz-2Py)2] (LnIII = GdIII 3, TbIII 4, DyIII 5, HoIII 6). The nine-coordinated LnIII ions with C 4v symmetry in 1 and 2 are linked by the NIT-4trz-2Py ligand through a “head-to-tail” mode, leading to a 1D structure. Compounds 3–6 possess a linear trinuclear structure which contains two {LnIII–radical} chelating units and one Dy­(hfac)3 (ligated by two triazole groups). All LnIII centers in 3–6 are in eight-coordinate D 4d geometry. Magnetic studies reveal that slow magnetization relaxation occurs in the two DyIII-containing compounds. No maxima of χ″ are observed for complex 2 while compound 5 presents visible maxima in frequency-/temperature-dependent χ″ signals, which is due to the optimization of symmetries around DyIII ions from C 4v in 2 to D 4d in 5. For luminescent spectra, two TbIII-based derivatives display characteristic emissions of TbIII ions at room temperature.

Key indicators: single-crystal X-ray study; T = 296 K; mean (C-C) = 0.003 Å; R factor = 0.019; wR factor = 0.041; data-to-parameter ratio = 15.1.In the title complex, [Nd(C 10 H 13 N 2 O 8 )(H 2 O)] n , each Nd III ion is coordinated by six O atoms and two N atoms from one N 0 -(carboxymethyl)ethylenediamine-N,N,N 0 -triacetate (edta) ligand and one water molecule, displaying a bicapped trigonal-prismatic geometry. The edta ligands link the neodymium metal centres, forming polymeric chains running along the a axis of the unit cell. These chains are further assembled via intermolecular O-HÁ Á ÁO hydrogen-bonding interactions into a three-dimensional supramolecular network. Related literature

Two novel inorganic-organic hybrids containing the pyramidal SbO group in Dawson-like POMs based on an organic ligand with different coordination modes, namely {Ni(phen)}[SbWO]·(HO)·7HO (1) and [Cu(phen)(HO)]{[Cu(phen)(HO)][SbWO]}·2HO (2) (phen = 1,10-phenanthroline), have been synthesized. The catalytic property of compound 1 was studied as the first case for an {M} cluster containing the pyramidal SbO group. Remarkably, compound 1 has excellent photocatalytic activity for RhB degradation and the probable mechanism of degradation was discussed. Additionally, the 2D-IR correlation spectra (2D-IR COS) under magnetic perturbation were recorded to analyze the magnetic properties of compound 1. The 2D-IR COS under thermo perturbation were recorded to verify the presence of H-bonding interactions.

Employing a new nitronyl nitroxide biradical NITPhPzbis(NITPhPzbis = 5-(1-pyrazolyl)-1,3-bis(1’-oxyl-3’-oxido-4’,4’,5’,5’-tetramethyl-4,5-hydro-1H-imidazol-2-yl)benzene), a series of 2p-4f complexes [Ln2(hfac)6(H2O)(NITPhPzbis)] (LnIII = Gd1, Tb2, Dy3; hfac = hexafluoroacetylacetonate) were successfully synthesized. In complexes 1–3, the designed biradical NITPhPzbis coordinates with two LnIII ions in chelating and bridging modes to form a four-spin binuclear structure. Direct-current magnetic study of Gd analogue indicates that ferromagnetic exchange exists between the Gd ion and the radical while antiferromagnetic coupling dominates between two mono-radicals. Dynamic magnetic data show that the χ” signals of complex 3 exhibit frequency dependence under zero field, demonstrating slow magnetic relaxation behavior in complex 3. And the estimated values of Ueff and τ0 are about 8.4 K and 9.1 × 10−8 s, respectively.