Determining the total structure of metal nanoparticles is vital to understand their properties. In this work, the first all-alkynyl-protected Ag nanocluster, Ag(C≡CPh), was synthesized and structurally characterized by single crystal diffraction. Ag atoms are arranged in a Ag@Ag@Ag three shell structure and all 44 phenylethynyl ligands coordinated with Ag in a μ mode. In spite of being absent in nanocluster, P NMR study reveals that bidentate phosphine first reacts with Ag(I) to form a dinuclear complex, from which Ag atoms are then released to phenylethynyl ligands. This phosphine mediated strategy may find general application in synthesis of alkynyl-protected Ag nanoclusters.

A new luminescent entangled (srs nets with two-fold interpenetration, linked via short Cu/Cu distances of ca. 2.8 Å) MOF, namely, [(CuCN) 3 L$(guest) x ] n (L ¼ 2,6-bis((3,5-dimethyl-1H-pyrazol-4-yl)methyl)pyridine; x ¼ 1 or 2), which contains microporous channels, is synthesized. This MOF material shows structural dynamics upon adsorption of various volatile organic solvent molecules, accompanied by reversible guest responsive colour changes of the fluorescence emission that are discernible by the naked eyes. The vacuated form of this material can also exhibit qualitative solvate-optical sensing behaviours toward various mixed solvents.Moreover, a quantitative real-time monitoring device is constructed that implements the determination of acetonitrile vapour pressure through optical response, which causes a drastic emission change from blue to yellow. The detailed structural elucidation provides structure-property understanding for the host-guest responsive dynamics.

A supramolecular dual emissive system incorporating two classical copper(I)-cluster-based luminophores, namely, Cu(4)I(4) and Cu(3)Pz(3) (Pz = pyrazolate), is reported. The targeted luminescent coordination polymer exhibits reversible thermochromism spanning from green to orange-red.

A novel hydrophobic metal-organic framework (MOF), namely Cu2 L (L = 3,3',5,5'-tetraethyl-4,4'-bipyrazolate), is synthesized through a stepwise method, and exhibits an unprecedented 3,4-c net. The exceptionally thermal, chemical, and air stability of this MOF, especially in water and under acidic or basic conditions, and its selective and fast sorption capacity for hydrocarbons over water warrant its direct use for efficient removal of trace organic wastes (e.g. benzene, toluene, xylene, and mixtures thereof) from contaminated water.

Luminescence mechanochromism of the well-known Cu3Pz3-type (Pz = pyrazolate) complexes is reported here, which is unusual for this family. Two types of new Cu3Pz3 complexes, namely Cu3(EBPz)3 (1; EBPz = ethyl-4'-benzoate-3,5-dimethylpyrazolate) and Cu3(MBPz)3 (polymorphs 2a-c; MBPz = methyl-4'-benzoate-3,5-dimethylpyrazolate), have been synthesized and characterized. Their crystal structures exhibit a similar chairlike dimer stacking supported by short Cu···Cu contacts, which would facilitate the formation of photoinduced excimers. The dual emission from the organic fluorophore and excimeric copper cluster phosphor is found to undergo mechanically induced intensity switching between their high-energy (HE) and low-energy (LE) bands. Specifically, the relative intensities of crystalline samples are HE > LE, while the ground solid samples show LE > HE, resulting in the overall emission color interchanging between bluish violet and red. This switching can be reversed by application of solvent to the ground samples, presumably due to recrystallization, and also by heating. TD-DFT calculations reveal that the emissive singlet ligand localized state (S1) and triplet cluster centered state (T8) lie close in energy (separated by a gap of 0.1788 eV), suggesting the feasibility of dual emission and the possibility of reverse intersystem crossing, consistent with the long fluorescent lifetimes (10(2) ns scale) of the HE bands.