A new inorganic-organic photoluminescent material constructed with helical [Zn(3)(mu3-OH)(mu2-OH)] chains

Metal-Organic Frameworks for Liquid Phase Applications

In the last two decades, metal-organic frameworks (MOFs) have attracted overwhelming attention. With readily tunable structures and functionalities, MOFs offer an unprecedentedly vast degree of design flexibility from enormous number of inorganic and organic building blocks or via postsynthetic modification to produce functional nanoporous materials. A large extent of experimental and computational studies of MOFs have been focused on gas phase applications, particularly the storage of low-carbon footprint energy carriers and the separation of CO2-containing gas mixtures. With progressive success in the synthesis of water- and solvent-resistant MOFs over the past several years, the increasingly active exploration of MOFs has been witnessed for widespread liquid phase applications such as liquid fuel purification, aromatics separation, water treatment, solvent recovery, chemical sensing, chiral separation, drug delivery, biomolecule encapsulation and separation. At this juncture, the recent experimental and computational studies are summarized herein for these multifaceted liquid phase applications to demonstrate the rapid advance in this burgeoning field. The challenges and opportunities moving from laboratory scale towards practical applications are discussed.

1D ladder and 2D bilayer coordination polymers constructed from a new T-shaped ligand: luminescence, magnetic and CO2 gas adsorption properties

1D ladder and 2D bilayer coordination polymers are constructed by using a new T-shaped ligand, in which the 2D bilayer exhibits CO₂ gas adsorption features.

Self-Assemblies of Zinc Complexes for Aggregation-Induced Emission Luminogen Precursors

Positional isomers of zinc-nitrobenzoate complexes possessing pyridine -3-(or-4-) carboxamide are used for a comparative theoretical and experimental study to understand their utility as model complexes to understand the role of metal-to-ligand charge transfer in aggregation-induced emission (AIE). Among the five different model zinc complexes, four of them are non-ionic, and one is an ionic complex. The frontier molecular energy levels of different combinations of the positional isomeric complexes and the absorption maximum were ascertained by density functional theory calculations. The PolyQ value obtained from solid samples of each complex is different. Shifts in the emissions to higher wavelengths than the expected emission for the S₁ to S₀ transition were observed due to aggregations. The highest value of PolyQ among the complexes was 13.56% observed for emission at 439 nm (λ_ex = 350) of the non-ionic complex, namely, (di-aqua)bis(pyridine-3-carboxamide)di(2-nitrobenzoato)zinc(II) monohydrate. Close resemblance in emission lifetime decay profiles of the solid samples of those complexes and the respective solutions of those complexes in dimethyl sulfoxide with or without water showed a common trend, suggesting aggregation-induced emission in each case. Aggregation-induced emission caused by adding water in dimethyl sulfoxide solution of each complex showed an initial increase without a shift in the emission wavelength followed by a quenching with a shift of the respective emission peak to a short wavelength. Dynamic light scattering studies showed an increase in the average particle sizes upon an increase in the concentration of water. This indicated initial participation of water molecules to form aggregates with the complexes, favoring an increase in the AIE intensity. Aggregation of each complex changes with the concentration of water, and an increase in the concentration of water beyond a characteristic limit causes lowering of the emission intensity to the short wavelength.

“Pinwheel” subunit-directed polyoxometalate-based hybrid compound [Cu(bimb)2]2[β-Mo8O26] with both helixes and chiral layers

An unprecedented hybrid octamolybdate-based compound with both chiral and helical structure, consisting of a pair of enantiomorphous chiral “pinwheel” subunits, has been synthesized and its photocatalytic properties have been investigated.

Three luminescent metal–organic frameworks constructed from trinuclear zinc(ii) clusters and furan-2,5-dicarboxylate

Three metal–organic frameworks constructed from trinuclear zinc(ii) clusters and furan-2,5-dicarboxylate with different topology were hydrothermally synthesized by adjusting the anions and solvent. Moreover, the blue luminescence of the complexes was investigated.

A rare I2O3 hybrid organic–inorganic material with high connectivity and quadruple-stranded helices

A novel I²O³ hybrid material with one Cd–OH helix, two quadruple-stranded Cd–ligand helices and a (5,14-c) topological net was assembled.

Structural diversities in Cu(i) and Ag(i) sulfonate coordination polymers and their anion exchange properties

Cu(i)/Ag(i) sulfonate CPs have been synthesized and characterized. One of the CPs exhibits a reversible anion exchange for perchlorate and permanganate.

Self-assembly, crystal structures and properties of metal–3,4,5-tris(carboxymethoxy)benzoic acid frameworks based on polynuclear metal-hydroxyl clusters (M = Zn, Co)

Three new inorganic–organic frameworks based on 3,4,5-tris(carboxymethoxy)benzoic acid and polynuclear metal-hydroxyl clusters were assembled. Photoluminescent and magnetic properties are investigated.