A series of metal–organic frameworks based on polydentate Schiff-base ligands derived from benzil dihydrazone: synthesis, crystal structures and luminescent properties

Abstract

) and [ZnL 2 2 (NCS) 2 ] n (8) have been synthesized and structurally characterized by IR spectroscopy, UV spectroscopy, thermogravimetric (TG) analyses, luminescent spectroscopy and complete single-crystal structure analyses, where L 1 is (N 0 ,N 0 -bis[1-(pyridin-4-yl)methylidene]benzil dihydrazone) and L 2 is (N 0 ,N 0 -bis[1-(pyridin-3yl)methylidene]benzil dihydrazone), respectively. The structure of 1 exhibits a two-dimensional layer network featuring trimetal 36-membered non-planar macrocycles. Polymer 2 is a one-dimensional chain structure with tetranuclear metallacyclic rings. For polymer 3, each ligand acts as a bidentate ligand to bind two Ag(I) centers and each silver center is coordinated to two N-donors from two ligands forming a one-dimensional chain. Polymer 4 displays a two-dimensional layer network containing tetranuclear 68-membered metallocyclic rings. 8) show all one-dimensional chain structures containing bimetallic 8-membered rings and tetrametallic 42-membered rings for 5, bimetallic 34-membered quadrangular rings for 6 and 7, and bimetallic 30-membered quadrangular rings for 8, respectively. The luminescent properties of L 1 , L 2 and 1-8 in the solid state were investigated.

Understanding Hysteresis in Carbon Dioxide Sorption in Porous Metal–Organic Frameworks

“…The emission spectra of as-synthesized 2 shows band at 420 nm, assigned to intra-ligand pyridinedicarboxylate-centered electronic transition. Thus, the electron ligand-to-metal charge transfer was observed only in the case of compound 1, since d-orbitals of Mn centers can participate in the charge transfer, 41,42 while charge-transfer emission is not characteristic for the compounds of s-elements such as Mg. Removal of guest water and DMF molecules was achieved by soaking 1 and 2 in acetone for several days and then placed under vacuum at ambient conditions.…”

A novel tetraphenylethylene derivative: 4-methyl-N-[3-(1,2,2-triphenylethenyl)phenyl]benzenesulfonamide with aggregation-induced emission

“…The three-dimensional (3D) network ( Fig. 6) propagates along the c axis formed from the 2D sheets by means of C1-H1Á Á Á interactions, with a distance between the H atom (C25-H) and the centre of the C28-C33 aromatic ring of 3.297 (1) Å (Bai et al, 2010).…”

One New Inorganic-Organic Hybrid Polyoxometalate [(NH3C6H4)2SO2]2SiMo12O40·2CH3CN·CH3OH·2H2O: Synthesis, Crystal Structure, and Luminescent Properties

“…[25,26] To enrich the fluorescent database of this type, the luminescent properties of the title compound and 4,4 -diaminodiphenylsulfone were investigated in H 2 O at the room temperature. As shown in Figure 6, the compound 1 shows the two emission peaks at 339 nm and 440 nm upon excitation at 276 nm.…”