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One mononuclear complex [Dy(Htpy)(NO3)2(acac)] (1) and a tpy--extended 1D chain {[Dy(CH3OH)(NO3)2(tpy)]·CH3OH}n (2) (Htpy = 4'-(4-hydroxyphenyl)-2,2':6',2''-terpyridine, Hacac = acetylacetone) were successfully designed to investigate the effect of bond length tuning around the DyIII cation on the magnetic dynamics of single-molecule magnets (SMMs). Interestingly, two magnetic entities possess the same local coordination sphere (N3O6-donor) as well as the configuration (Muffin, Cs) of dysprosium centers. Only a slight difference in structure results from purposefully substituting the acetylacetone ligand in 1 with hydroxyl oxygen from tpy- linkage and one methanol molecule in 2. However, the remarkable differences in dynamics behavior were clearly found between them. Compound 1 possesses a thermal-activated effective energy barrier (Ueff/kB) of 22.7 K under a 0 kOe direct current (dc) field and negligible hysteresis loop at 2.0 K, while complex 2 shows high-performance SMM behavior with the largest energy barrier of 354.36 K among the reported nine-coordinated DyIII-based systems and the magnetic hysteresis up to 4.0 K at a sweep rate of 200 Oe s-1. These experimental results combined with the previous reported data reveal that the shortest bond and the bond length difference around the DyIII center synergistically determine the dynamics of SMMs. The uniaxial anisotropy increases with the decrease of the shortest bond and the increase of the bond length difference, which is confirmed by the theoretical calculations.

A versatile microporous metal-organic framework (MOF), {[Cu(TIA)]·1.5CH3OH}n (Cu-1), was successfully obtained via the solvothermal reaction of cuprous(II) salt with the bifunctional ligand 3-(1H-1,2,4-triazol-1-yl)isophthalic acid. Single-crystal X-ray diffraction studies indicate that Cu-1 contains an apo three-dimensional skeleton and two types of one-dimensional channels. The framework of Cu-1 has excellent acid-alkali resistance and thermal stability, which is stable in a pH = 2-13 aqueous solution and an 260 °C air environment. In addition, the microporous copper MOF shows very high uptakes of CO2 (180 cm3·g-1) and C2H2 (113 cm3·g-1) at 273 K and displays excellent adsorption selectivity for small molecular gases. The ideal adsorbed solution theory selectivity values for C2H2/C2H4, CO2/CH4, and CO2/N2 are 2, 9, and 22 at 298 K, respectively. At the same time, breakthrough experiments for CO2/CH4, CO2/N2, and C2H2/C2H4 were further conducted to verify the efficient separation performances.

Photodegradation of organic dyes over coordination polymer (CP) photocatalysts has become one of the effective strategies for the prevention and control of water pollution, in which the energy band...

Three unique [Cu4(μ3-OH)2]6+ core-based magnetic complexes, [Cu4(amtrz)2(μ3-OH)2(nb)6]·2H2O (1), {[Cu5(H2O)6(trz)2(μ3-OH)2(btc)2]·0.6H2O}n (2), and {[Cu5(H2O)2(Htrz)2(μ3-OH)2(btec)2]·0.125H2O}n (3)...