Chunfeng Yan

A polynuclear d10-d10 metal complex with unusual near-infrared luminescence and high thermal stability.

Three d(10)-d(10) transition-metal complexes with organosulfur ligands, Cu(6)(btt)(6) (1), Cu(4)(btt)(4) (2), and Ag(6)(bmt)(6) x 6 THF (3) (Hbtt = 2-benzothiazolethiol, Hbmt = 2-benzimidazolethiol, and THF = tetrahydrofuran), were synthesized and characterized. Complexes 1 and 2 with similar coordination environments are isomers crystallized from the same solvothermal reactions, but they cause great differences in both the structures and luminescent behaviors. The hexanuclear cluster 1 exhibits unusual near-infrared luminescence and high thermal stability, while complex 2 with tetranuclear cores and stronger metal-metal bonds shows an intense red emission like that from complex 3.

Thermally stable helical chain and octanuclear Ag(I) coordination networks with yellow luminescence

The reactions of 2,4,6-tri(2-pyridyl)-1,3,5-triazine (tpt) and Ag(I) ions under solvothermal or solvent evaporation conditions yielded three new coordination complexes with the interesting frameworks: [Ag(tpt)(NO3)]n (1), [Ag2(tpt)(NO3)(PPh3)2(H2O)](NO3)·2H2O (2), [Ag8(tpt)4(NO3)4(µ2-CN)2](NO3)2 (3) (PPh3= triphenylphosphine). Complex 1 crystallizes in a chiral space groupP212121, giving a 1D chain and left-handed helical structure which is the first example of metal-tpt complexes with helical chains. Through the π–π interactions and C–H⋯O hydrogen bonding, the 1D chains of 1 further form a 3D supramolecular structure. Dinuclear complex 2 gives a 3D network via intramolecular O–H⋯O and C–H⋯O hydrogen bonding, while the octanuclear complex 3 affords a 2D framework through weak Ag⋯Ag interactions and van der Waals force. Complexes 1 and 3 exhibit high thermal stabilities at 350 and 300 °C, respectively, and both display unusual yellow luminescence in the crystal-state at cryogenic temperature.

Crystal Structures and Luminescence Behaviour of d 10 Metal)Organic Complexes with Multipyridine Ligands

Six d10 metal–organic complexes with multipyridine ligands, [Cd(terpy)2](NO3)2·2H2O (1), [Cd(terpy)(NO3)2(H2O)] (2), [Hg(terpy)I2] (3), [Zn(tpt)(NO3)(H2O)2]NO3 (4), [Zn2(tpt)2(4,4′-bipy)(4H2O)](NO3)4·4H2O (5), [Zn(tpt)(OAc)2]·5H2O (6) (terpy = 2,2′:6′,2′-terpyridine, tpt = 2,4,6-tri(2-pyridyl)-1,3,5-triazine, 4,4′-bipy = 4,4′-bipyridine) were synthesized and structurally characterized. The abundant hydrogen-bonding interactions extend complex 2 into ladder-like 1D chains, discrete molecules of 4 into a 2D layer structure, complex 5 into a 2D hydrogen-bonded network through linking the hydrogen-bonded ribbons with hexagonal and four-sided rings, and complex 6 into a 3D hydrogen-bonded network through combining water helical chains. Fluorescence analyses of 1–6 in the solid state are investigated at both room temperature and 10 K. The emission spectra of 1–2 show a large red shift, which is ascribed to ligand-to-ligand charge transfer combined with ligand-to-metal charge transfer, whereas emissions of 4–6 all originate from intraligand π-π* transitions. In organic solvents, 1–6 behave very differently and their emission spectra exhibit various luminescences, with an obvious blue shift indicating strong solvent effects. The X-ray diffraction and thermal gravimetric analyses for complexes 1–6 are also reported.