We report the synthesis and structural diversity of Zn(II) metal-organic framework (MOF) with in situ formation of tetrazole ligand 3-ptz [ 3-ptz = 5-(3-pyridyl)tetrazolate] as a function pH. By varying the initial reaction pH, we obtain high-quality crystals of the noncentrosymmetric three-dimensional MOF Zn(3-ptz) 2 , mixed phases involving the zinc-aqua complex [Zn(H 2 O) 4 (3-ptz) 2 ]·4H 2 O, and two-dimensional MOF crystals Zn(OH)(3-ptz) with a tunable microrod morphology, keeping reaction time, temperature, and metal–ligand molar ratio constant. Structures are characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and UV–vis spectroscopy. We discuss the observed structural diversity in terms of the relative abundance of hydroxo-zinc species in solution for different values of pH.

In the present work, the synthesis and structural characterization of four new polyoxovanadoborate (BVO) frameworks based on the [V12B18O60H6](10-) polyanion are reported: (NH4)8(1,3-diapH2)[V12B18O60H6]·5H2O (1), K8(NH4)2[V12B18O60H6]·18H2O (2), K10[V12B18O60H6]·10H2O (3) and K8Cs2[V12B18O60H6]·10H2O (4). A global antiferromagnetic behaviour is observed for these 10V(IV)/2V(V) mixed valence clusters. The magnetic data of 1, 2 and 3, which present different countercation environments, show that 1 is more coupled than 2 and 3. DFT calculations show that the positive charges strongly influence the polarization mechanism of the spin density of the vanadyl groups and the extent of the magnetic orbitals, therefore corroborating the experimental observation of the quenching effect of the magnetic coupling between vanadium centres of 2 and 3.

Magnetic analogues of Alq3 give rise to molecular/ferromagnetic interfaces with specific hybridization, opening the door to interesting spintronic effects.

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The plasticity of the coordination chemistry of lanthanoid ions has allowed the design and synthesis for the first time of a family of mononuclear hybrid organic–inorganic lanthanoid complexes with slow relaxation of the magnetization.

Experimental redox potentials of the couples [Cu(R-L ( n ))(CH 3CN)] (2+,+), where L (1) is bis-(pyridine-2-ylmethyl)-benzylamine, L (2) is (pyridine-2-ylethyl)(pyridine-2-ylmethyl)-benzylamine, and R is H, Me, or CF 3, were determined in dichloromethane solution. The compounds exhibited one simple quasi-reversible wave over the measured potential range of -500 to +1200 mV, and the E 1/2 values varied from +200 to +850 mV versus SCE. These experimental values were correlated with redox potentials calculated using density functional theory. The optimized geometries and the predicted redox potentials were obtained using the BP86 functional and a combination of the basis sets LACV3P** (for Cu) and cc-pVTZ(-f) (for light atoms). A distortion analysis of all of the optimized geometries for both oxidation states was performed using the generalized interconversion coordinate phi. A linear relation was obtained between this parameter and the redox potentials. However, the [Cu(CF 3-L (1))(CH 3CN)] (+) complex showed the largest deviation, which was explained by the more-rigid structure of the ligand.

We report the design, preparation and characterization of two families of thermally robust coordination complexes based on lanthanoid quinolinate compounds: [Ln(5,7-Br 2 q) 4 ]and [Ln(5,7-ClIq) 4 ] -, where q = 8-hydroxyquinoline and Ln = Dy III , Tb III , Er III and Ho III . Samples of [Dy(5,7-Br 2 q) 4 ]decompose upon sublimation, whereas the sodium salt of [Dy(5,7-ClIq) 4 ] -, which displays subtly different crystalline interactions, is sublimable under gentle conditions. The resulting film presents low roughness with high coverage and the molecular integrity of the coordination complex is verified through AFM, MALDI-TOF, FT-IR and microanalysis. Crucially, the single-molecule magnet behavior exhibited by [Dy(5,7-ClIq) 4 ]in bulk remains detectable by ac magnetometry in the sublimated film.

Mononuclear organic–inorganic hybrid lanthanoid complexes show that the combination of both types of ligands improves the optical response compared to the inorganic analogue, thus having potential optical applications due to their thermal response.