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A brand-new application of thorium-bearing clusters in the field of ionizing radiation detection is exemplified by two novel hexanuclear thorium clusters, Th-bppCOO-1 and Th-bppCOO-2, which incorporate carboxylate-functionalized 2,6-di(pyrazol-1-yl)pyridine ligands. Notably, Th-bppCOO-1 is composed of an unprecedented [Th6(OH)4O4(H2O)5]12+ secondary building unit, the Th6 core of which is decorated by five H2O molecules. Furthermore, selective photoluminescence quenching responses of Th-bppCOO-1 and Th-bppCOO-2 toward X-ray over UV radiation have been demonstrated for the first time.

Effective disposal of radioactive iodine has been a persistent challenge in nuclear fuel recycling. Herein, we synthesized a series of micro-/mesoporous hierarchical adsorbents by the zeolitic imid...

Decarbonylation of the experimentally known CpRu(CO)2(η1-C5H5), CpMo(CO)2(η3-C7H7), and CpNb(CO)2(η4-C8H8) (Cp = η5-C5H5), each with uncomplexed 1,3-butadiene units in the CnHn ring, as well as the related CpTc(CO)2(η2-C6H6), to give the corresponding carbonyl-free derivatives CpM(ηn-CnHn) derivatives has been studied by density functional theory. For ruthenium, technetium, and molybdenum the coordinated CnHn ring of the intermediate monocarbonyl CpM(CO)(ηn–2-CnHn) contains an uncomplexed C═C double bond and each decarbonylation step proceeds with a significant energy barrier represented by a higher energy transition state. However, decarbonylation of CpNb(CO)2(η4-C8H8) to the monocarbonyl proceeds without an energy barrier, preserving the tetrahapto coordination of the C8H8 ring to give CpNb(CO)(η4-C8H8) in which the niobium atom has only a 16-electron configuration. All of the monocarbonyl derivatives CpM(CO)(CnHn) are predicted to be strongly energetically disfavored with respect to disproportionation ...

A facile synthesis procedure was built to synthesize zeolitic imidazolate frameworks (ZIFs) ZIF-8 and ZIF-69 under ambient conditions with the prevention of organic solvents. ZIF-69 adsorbent was first introduced in the liquid-phase separation of hexane isomers. A sieving test was carried out using samples of n-hexane (nHEX) or 2-methylpentane (2MP) over two ZIFs and commercial 5A zeolite materials. According to batch adsorption performances and modeling, ZIF-8 exhibits the highest adsorption selectivity and capacity for nHEX, followed by ZIF-69 and 5A zeolite. The equilibrium data at 25 °C show that a significant amount (0.51 g/g) of nHEX and only 0.09 g/g 2MP can be adsorbed in ZIF-8. And the maximum adsorption capacity of nHEX and 2MP on ZIF-69 are 0.34 g/g and 0.10 g/g, respectively. Breakthrough experiments performed at 150 °C with a binary mixture of nHEX/2MP confirm the shape selectivity and adsorption capacities of ZIF-8 toward nHEX at various total pressures from 0.5 to 1.3 MPa and with different...

A metal- and base-free protocol for one-pot synthesis of 2,5-diaryl 1,3,4-oxadiazoles via a radical-promoted cross-dehydrogenative coupling strategy was developed. This reaction involved the N-acylation of aryl tetrazoles with aryl aldehydes, followed by thermal rearrangement. A wide range of aryl tetrazoles and aryl aldehydes survived the reaction conditions to deliver the corresponding products in moderate to good yields.

A straightforward strategy is designed for the fabrication of CuFe2O4-graphene heteroarchitecture via a one-step hydrothermal route to allow multifunctional properties, i.e., magnetic cycling, high photocatalytic activity under visible light irradiation, and excellent electrochemical behaviors for use as the anode in lithium-ion batteries (LIBs). Transmission electron microscopy (TEM) observations indicate that graphene sheets are exfoliated and decorated with hexagonal CuFe2O4 nanoflakes. The photocatalytic activity measurements demonstrate that the combination of CuFe2O4 and graphene results in a dramatic conversion of the inert CuFe2O4 into a highly active catalyst for the degradation of methylene blue (MB) under visible light irradiation. CuFe2O4 nanoparticles themselves have excellent magnetic properties, which makes the CuFe2O4-graphene heteroarchitecture magnetically recyclable in a suspension system. It should be pointed out that the CuFe2O4-graphene (with 25 wt % graphene) heteroarchitecture as a...

Two chiral d10 metallosupramolecular systems based on an achiral fluorinated Schiff-base ligand have been prepared and characterized. The ZnII complex 1 reveals 21 helical coordination chains with ...

A series of novel metal–organic frameworks (MOFs) have been assembled from PbII and 2,3,5,6-tetrachloro-1,4-benzenedicarboxylic acid (H2BDC-Cl4) by simply adding different alkali metal ions as templates. When only lead nitrate is used, a robust 3D open framework [Pb(BDC-Cl4)(MeOH)2]n (1) with pts topology can be obtained. Incorporating the lighter LiI or NaI ions into the above PbII/BDC-Cl4 system results in two unique isostructural 3D PbII–LiI and PbII–NaI heterometallic frameworks, {[PbLi2(BDC-Cl4)(μ2-OH)2](H2O)}n (2) and [PbNa2(BDC-Cl4)(μ2-OH)2]n (3), which are built from the combination of a 3D rod-packing PbII-carboxylate framework and a 3D NaI–BDC-Cl4 (or LiI–BDC-Cl4) network. When the heavier KI ion is applied, the similar reaction affords a 3D MOF [Pb2(BDC-Cl4)2(DMF)3]n (4), which represents the first pillar-layered PbII coordination network with a (3,5)-connected gra topology. The results illustrate the powerful effect of the alkali-metal templates in MOFs assemblies. The solid-state properties s...

With solvent molecules participating in coordination systems, four new MnII coordination polymers of the rigid ligand 2,3,5,6-tetrachloro-1,4-benzenedicarboxylic acid (H2BDC-Cl4) have been obtained from different solvent media. Single-crystal X-ray analysis indicates that the coordination arrays of 1−4 vary from 1D fishbone or zigzag chain for 1 or 2, 2D (4,4) layer for 3, to 3D SrAl2 coordination network for 4, respectively. In {[Mn(BDC-Cl4)(py)2(H2O)2](py)2}n (1) and {[Mn(BDC-Cl4)(MeOH)3](MeOH)}n (2), pyridine/water (in 1) and MeOH (in 2) molecules act as the monodentate terminal ligands to fulfill the metal coordination spheres. In the case of {[Mn(BDC-Cl4)(dioxane)(H2O)2](dioxane)}n (3), the aqua ligand is monodentate and the dioxane moiety displays unusual bridging bidentate mode, whereas for [Mn5(BDC-Cl4)5(DMF)5]n (4), three MnII centers are connected by four BDC-Cl4 ligands and two DMF molecules to constitute a trimeric unit. These secondary units are extended to the final 3D network with SrAl2 (sr...