Gongzhen Cheng

Spectroscopic and theoretical studies on copper(II) complex of maleinitriledithiolate and 1,10-phenanthroline

A complete vibrational spectra analysis of the title complex is performed in this paper. The molecular geometry, binding, electron structure and spectroscopic properties for the title complex are studied in detail by PM3 or ZINDO/S method. It has been found that this complex has a planar structure belonging to the symmetry point group C2v and its ground state is the spin doublet state. By comparison with the observed results, it can be concluded that PM3 methods are reliable to calculate the vibrational spectra of this molecule. It is worth noting that the scientific method of assigning vibrational spectra for a complicated molecule containing metal is established herein for the first time by giving main fixed points and pivotal vibrational units. Besides the regular symbols, the new defined symbols eta and M play an important role in describing the vibrational modes accurately and vividly.

The synthesis and characterization of dinuclear ruthenium sensitizers and their applications in photocatalytic hydrogen production.

A dinuclear ruthenium(II) dye sensitizer, ([Ru(2)(bpy)(4)BL](ClO(4))(2)) referred as Compound 1, where bpy=2,2-bipyridine, BL=2,2-((1E,1E)-(((E)-diazene-1,2-diyl-bis(2,1-phenylene))-bis(azanylylidene))-bis (methanylylidene)) diphenol (a bidentate bridging ligand), was designed, synthesized and characterized. The dye sensitizer was used on the photocatalytic water splitting for hydrogen (H(2)) production over TiO(2) (P25) under visible light (λ≥400 nm) irradiation using triethanolamine (TEOA) as a sacrificial electron donor. The dye sensitized-TiO(2) demonstrated a good stability and sufficient reproducibility for over 6 h. The photosensitization ability of the sensitizer was due to its conjugation system, large molecular area, TiO(2) linkage mode and the antenna effect.

Synthesis and crystal structure of maleonitriledithiolate metal complexes with N-methylacridine as cations

Abstract The synthesis of [N-MeA]2[M(mnt)2] (N-MeA=N-methylacridine; M=Ni (II), Zn (II), Cu (II) and Cd (II); mnt=maleonitriledithiolate) and crystal structure analysis of the Ni (1) and Zn (2) complexes are reported. The conductivities of almost all the complexes under 4 MPa pressure are above 10−5 S cm−1, which are characteristic of intrinsic semi-conductors. The complexes exhibit charge transfer transitions in both their absorption spectra and fluorescence spectroscopy.

The synthesis, crystal structure and spectroscopic properties of luminescent Zn(II) complex.

A luminescent Zn(II) complex 1, ZnL2Cl2.2H2O has been synthesized where L=2,2,2-(1,3,5-benzenetriyltrimethylidyne) as a yellow crystal. Single crystal X-ray analysis of the compound 1 shows a distorted tetrahedral structure. The compound 1 crystallizes in monoclinic, space group C2/c with a = 20.3151(19), b = 8.7299(9), c = 24.626(2) angstroms, beta = 107.474(2) degrees , V = 4165.9(7) A3. At room temperature, the complex 1 exhibits an intense blue emission at 474 nm upon 380 nm excitation.

Synthesis, spectra and X-ray crystal structure of a new type of macrocyclic hexanuclear iron(III) cluster

A macrocyclic iron(III) 18-azametallacrown-6 compound, [Fe6(5-Brashz)6(H2O)6]u2009·u200920H2O(5-Brashzu2009=u2009N-acetyl-(5-bromosalicylhydrazide)), where the pentadentate ligands bridge the metal ions, was synthesized and characterized. Due to the meridional coordination of the ligand to the metal ion, the ligand is not only bridging the ring metal ions using a hydrazide N–N group, but also enforcing the stereochemistry of the metal ions as a propeller shape with alternating Λ/Δ configuration. The disc-shaped hexanuclear cluster is about 14.5u2009Å in diameter, 16.8u2009Å in thickness and has a vacant cavity in the center of the cluster.

A cucurbit[8]uril inclusion complex with 1,7-dimethyl-1,4,7,10-tetraazacyclododecane tetrachloride

The 1:1 inclusion complex between cucurbit[8]uril and protonated 1,7-dimethyl-1,4,7,10-tetraazacyclododecane tetrahydrochloride was prepared. Its structure was characterized using NMR and single crystal X-ray diffraction. This new macrocycle complex shows a beautiful sexfoil packing structure, very different from that of the free cucurbit[8]uril, which is perfectly aligned. A higher inclination angle of about 78° 15′ is observed between the two macrocycle planes.

Bent and linear trinuclear nickel complexes with ligands derived from N -acylsalicylhydrazide ligands: structural characterization and bioactivity

Two trinuclear Ni(II) complexes Ni3(L1)2(py)2(DMF)(H2O) (1) and Ni3(L2)2(py)2(DMF)2 (2) with two new trianionic pentadentate ligands N-(3,5-dimethylbenzoyl)-salicylhydrazide (H3L1) and N-(phenylacetyl)-5-nitrosalicylhydrazide (H3L2) have been synthesized and characterized by X-ray crystallography. Nickel ions in the two complexes have square-planar/octahedral/square-planar coordination. Central metal ion and two terminal metal ions in the two complexes are combined by two bridging deprotonated ligands, forming a trinuclear structural unit with an M–N–N–M–N–N–M core. Studies on the trinuclear Ni(II) complexes show that the β-branched N-acylsalicylhydrazide ligands with sterically flexible Cα methylene groups yield linear trinuclear Ni(II) complexes, while α-branched N-acylsalicylhydrazide ligands tend to form bent trinuclear Ni(II) complexes. Antibacterial screening data in a previous study indicates that bent trinuclear Ni(II) compound 1 is more active than linear compound 2 and less active than a tetranuclear nickel compound.

Role Of Solvent In Slurry Phase Reactions

There exists an optimal amount of solvent (generally water) that can be added to the slurry phase reaction between solid reactants; the reactivity and efficiency of such reactions are different from those without solvent or those with large amount of solvent. Obviously, the solvent plays a crucial role in the process of the reaction, and it is the key to the understanding of unique reactivity and high efficiency of such slurry phase reactions. The water molecule absorbed on the surface of solid reactants, which is called bound water, has uniquely different properties compared with bulk water. Surface hydroxylation resulting from bound water greatly influences the chemical activity of the surface, which could be playing a role as catalyst or as the initialization point for further reactions, so that the reactants can react easily and fast under a simple reaction condition.

A novel low symmetry sulfur containing porphyrazine: synthesis and its interaction with serum albumin

A novel low symmetry sulfur-containing porphyrazine, 5,23,28,32-octabutoxy-10,11,17,18-tetrahydro-[9,12,16,19]-tetrathiino-33H, 35H-dinaphtho-porphyrazine (OTTDP), was synthesized by mixed condensation and characterized by NMR, FAB-MS and UV-visible spectra; this complex was found to be low aggregation in organic solvents and can interact with the serum albumin at several binding sites.