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The synthesis and crystal structures of two transition metal-based (Zn, Ni) coordination polymers comprising ligand molecules formed during hydrothermal treatment is described. The process involves dimerization via C-N bond formation for zinc, and C-C bond formation for nickel.

The DNA cleavage chemistry of a series of metallopeptides based on the amino-terminal Cu and Ni (ATCUN) binding motif of proteins is studied. The amino acid composition and stereochemistry of ATCUN metallopeptides have tuned the intrinsic reactivities of these systems as well as their overall structural features and both of these aspects have affected their reactivity and efficiency of DNA strand scission.

The experimental and density functional theory about the reaction of acetonitrile with a zerovalent nickel bis(dialkylphosphino)ethane fragment showed the C-CN bond activation to be favorable exclusively over C-H bond activation due to the strong thermodynamic driving force and slightly lower kinetic barrier.

Spectroscopic and quantum-chemical methods are used to study a set of substituted nickel porphyrin derivatives such as phthalocyanine and phenylporphyrin. The results show that the Ni(II) present in the phenylporphyrin structure is not affected by the change of the substituent like sulfonate or amino.

The substitution reactions at the nickel site of the cubane type [[([Ph.sub.3]P)Ni[Fe.sub.3][S.sub.4](L[S.sub.3])].sup.2-] clusters relevant to the C-clusters of carbon monoxide dehydrogenase were investigated. It was found that [[([Ph.sub.3]P)Ni[Fe.sub.3][S.sub.4](L[S.sub.3])].sup.2-] supports substitution reactions with phosphine displacement by thiolate ligands to yield clusters with tetrahedral or planar stereochemistry at the nickel site.

Based on the [Ni[(f-rac-L).sup.2+] and [[Ni[(CN).sub.4]].sup.2-] building blocks (L=5,5,7,12,12,14-hexamehtyl -1,4,8,11-tetraazacyclotetradecane), three helical supramolecular stereoisomers of meso-2, [DELTA]-2 and [DELTA]-3 were constructed. Complete examination of the structure indicates that the interchain hydrogen bonding and hydrophobic interactions play an important role in the transfer of chirality between neighboring helical chains due to which one dimensional (1D) helical chains are packed in an achiral or homochiral manner.

A gradient-corrected density functional method is used to study the influence of single impurity atoms on the structure, electronic, and magnetic properties of [Ni.sub.5] clusters. The most stable O[Ni.sub.5] isomers have exhibited a trigonal bipyramidal structure of the [Ni.sub.5] moiety with the impurity coordinated at a facet, ([[mu].sub.3]-O)[Ni.sub.5], or at an apex edge, ([mu]-O)[[Ni.sub.5], suggesting that ionization potentials and electron affinities of the clusters with impurity atoms have decreased with the coordination number of the impurity.

The melting of [Ni.sub.N] clusters, where N = 29, 50-150 is investigated by using molecular dynamics (MD) simulations with a quantum corrected Sutton-Chen (Q-SC) many-body potential. The results have shown that latent heat of fusion is the dominant effect on the melting temperatures ([T.sub.m]).

A competitive fluorescence anisotropy (FA) assay was developed to study the interaction between HPNikR and the ureA gene promoter, which encodes urease, and provide evidence that HPNikR requires a second metal ion for DNA bindings. The study results show that for HPNikR to bind to [P.sub.ureA], a square planar metal ion [Ni(II) or Cu(II)] must be coordinated to the high-affinity metal binding site and a divalent, hard metal ion [Mg(II), Ca(II), or Mn(II)] must be coordinated to an as yet unidentified low-affinity site.

The synthesis and characterization of N-confused porphyrin nickel complexes comprising an o-xylene fragment are described. One of the complexes consists of two porphyrinoid subunits, which have interacted despite the lack of coupling between the [pi]-electron systems, which is reflected by the redox and spectroscopic properties of the dimer.

A study is done to elucidate the impact of multiple-pulsed laser irradiation on Ni silicide formation in Ni(Ti)/Si system. The empirical outcomes suggest the probability of gaining an optimum laser annealing condition in producing NiSi film using multiple-pulsed laser annealing.

The structural, morphological, electrical, magnetic and elemental analyses correlated with the conductivity behavior are studied to understand the mechanism of conductivity of the nanocrystalline Ni[Fe.sub.2][O.sub.4]. The increase in conductivity is correlated with the concentration of the [Ni.sup.3} ions or cation vacancies, while the magnetic behavior combined with the semiconducting characteristics highlight their use as materials for ferrofluid and magnetic resonance imaging (MRI) contrast agent applications.

Preparations, crystal structures and spectral and magnetic properties of two new chiral one-dimensional cyanobridged coordination polymers [Cu.sup.II][L.sub.2][M.sup.II][(CN).sub.4].2[H.sub.2]O ( [M.sup.II] = N[i.sup.II] and [Pt.sup.II] ) are presented. Results show that these complexes are weak at antiferromagnetic interaction.

A study produced electroactive nanostructured films of chitosan (Ch) and tetrasulfonated metallophthalocyanines containing nickel (NiTsPc), copper (CuTsPc), and iron (FeTsPc) through the electrostatic layer-by-layer (LbL) technique. Results demonstrate that versatile electrodes could be prepared by incorporation of different metallophthalocyanine molecules in LbL films, which might be used in bionalaytical applications.

A study computed the adsorption and dissociation of thiophene on the MoP(001), [gamma]-Mo2N(100), and Ni2P(001) surfaces by using the density functional theory method. Results reveal that thiophene adsorbs dissociatively on MoP(001), while nondissociatively on [gamma]-Mo2N(100) and Ni2(001).

Nickel-doped and nitrogen-doped carbon nanocones with various amounts of buckling that feature square-planar, (approximate) tetrahedral, and octahedral coordination are designed. The optimized geometries and electronic structures of these novel metallocarbon complexes are calculated by employing the B3LYP and GGA-BLYP (ADF) exchange-correlation functionals.

Two-component triblock magnetic nanorods with gold end blocks and nickel interior blocks are synthesized and applied as affinity templates for the simultaneous and efficient separation of a three-component protein mixture. The analysis has shown that His-tagged proteins bind to nickel block and biotin-tagged proteins bind to the functionalized gold ends and each surface-bound protein can be released selectively using imidazole for the His-tagged protein and biotin for the biotinylated protein.

Mechanisms of oscillations and formation of nano-scale layered structure in induced co-deposition of some iron-group alloys Ni-P, Ni-W, Co-W were investigated. The results revealed that the electrodeposition induced co-deposition of the alloys has negative differential resistances NDRs from which the oscillations and the layer-structure formation arise.

Dinickel(II) complexes of the ligands N,N'-di-p-anisylformamidinate (DAniF) and N,N',N'-tripheynlguanidinate (TPG) are synthesized and crystallographically characterized, along with their one-electron oxidized analogues. In both systems, the Ni-Ni distances become shorter by ~0.1 A upon oxidation and it is proposed that this species contains a [Ni.sub.2.sup.6+] core with a single Ni-Ni sigma bond.

The synthesis of Ni[N.sub.2][S.sub.2] metalloligands, including the solid-phase synthesis of resin-bound Ni[(CGC).sup.2-], and sulfur-based derivatization with W[(CO).sub.5] and Rh[(CO).sub.2.sup.+] are carried out and described. Through comparison to analogous well characterized, solution-phase complexes, Attenuated Total Reflectance FTIR spectroscopy establishes the presence of unique heterobimetalic complexes both in solution and immobilized on resin beads.

The novel pyridine-containing 14 membered macrocycle 3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,-15-triene (L), which contains an N(sub 2)S(sub 2) donor set was synthesized and its protonation behavior was studied. The reactions between L and NiX(sub 2).6H(sub 2)O in ethanol or acetonitrile afforded the octahedral complexes and the square -planar complex [Ni(L)]-(X)(sub 2) were obtained by heating these octahedral complexes.

Reaction of the mononuclear Ni(II) thiolate complexes [Ni(L)] [L, [L.sup.1], [H.sub.2][L.sup.1], bis(2-mercaptoethyl)-1,2-dimercaptoethane; [L.sup.2], [H.sub.2][L.sup.2], N,N'-dimethyl-N,N'-bis (2-mercaptoethyl)-bis(aminoethyl)sulfide] with [FeCp[(CO).sub.2]l] gives the dithiolate-bridged heterobimetallic species, [Ni([L.sup.1])FeCp(CO)]P[F.sub.6], 1, and [Ni([L.sup.2])FeCp]I, 2, respectively. Binding of a Fe[(CO).sub.3] fragment via reaction of square-planar [Ni(pdt)(dppe)] (dppe, 1,2-diphenylphosphinoethane; [pdt.sup.2]-, 1,3-propanedithiolate) with [Fe.sub.3][(CO).sub.12] or [Fe[(CO).sub.3](BDA)] (BDA, benzylidene acetone) affords diamagnetic [(dppe)Ni([micro]-pdt)Fe[(CO).sub.3]], 3, in which the Ni(II) center is bound tetrahedrally to two thiolate S-donors and to two P-donors. The complex [(dppe)Ni([micro]-pdt)Fe[(CO).sub.3]], 3, reacts in solution via rearrangement to afford [(OC)Ni([micro]-dppe) ([micro]-pdt)Fe[(CO).sub.2]], 4, in which one P-donor of dppe is bound to Ni and the other to Fe, and a CO ligand has transferred from Fe to Ni. Additionally, the syntheses of 3 and 4 afford the side products [(dppe)Ni[(CO).sub.2]] and [[(OC).sub.3]Fe(pdt)Fe[(CO).sub.3]] together with the trinuclear species [(dppe)-(CO)Fe([micro]-CO)([micro]-pdt)Fe([micro]-pdt)Fe[(CO).sub.3]], 5. Reaction of [Ni(pdt)-(dppe)] with [FeCp[(CO).sub.2]I] in [CH.sub.2][Cl.sub.2] affords two products [(dppe)Ni([micro]-pdt)FeCp(CO)][PF.sub.6], 6, and [(dppe)Ni(pdt)([micro]-I)Ni(dppe)]-[PF.sub.6], 7. The complexes 2, 3, and 4 show Ni-Fe distances of 2.539(4), 2.4666(6), and 2.4777(7) [Angstrom], respectively, with relatively acute dihedral angles of 79.5-81.8[degrees] for the Ni-[S.sub.2]-Fe bridge, thus mimicking the shortened Ni ... Fe distance (2.5 [Angstrom]) and the acute dihedral angle of the Ni-[S.sub.2]-Fe moiety observed in certain active forms of [NiFe]hydrogenase. The role of direct Ni-Fe bonding in these complexes is discussed and linked to electronic structure calculations on [(dppe)Ni(pdt)Fe[(CO).sub.3]], 3, which confirm the presence of a bent Ni(dz2)-Fe([d.sub.[z].sub.2]) [sigma]-bond in a singlet ground state. hydrogenase | iron | nickel | thiolates | density functional theory calsulations

Nickel cation-acetylene complexes of the form Ni(super +)(C(sub 2)H(sub 2))(sub n), Ni(super +)(C(sub 2)H(sub 2))(sub Ne), and Ni(super +)(C(sub 2)H(sub 2))(sub n)Ar(sub M)(N=1-4) are produced in a molecular beam by pulsed laser vaporization. These ions are size-selected and studied in a time-of-flight mass spectrometer by infrared laser photodissociation spectroscopy in the C-H stretch region.

Vacataporphyrin, which belongs to the family of core-modified porphyrins and resembles the parent 5, 10, 15, 20 tetaarylporphyrin, reveals interesting properties as a ligand. The molecule coordinates through three nitrogen atoms and due to coordination the macrocycle acquires two fundamentally different conformations affording, eventually, different modes of weak transaction between the central metal ion and the butadiene fragment.

Ab initio and density functional theory (DFT) methods are applied to study the structures and kinetic stabilities of the possible products of the reactions of mononuclear nickel with (N2)(sub x) (x=1-4). The result suggests that side-on bound N2 ligand is ready to transform into the end-on bound one, while N4 ligand is hard to transform into side-on or end-on bound N2 ligand.

Neutral salicylaldiminato and cationic diimine complexes of Ni and Pd with different substituent patterns are studied by density functional theory to determine their propensity toward water complexation and hydrolysis of the growing chain. It is found that in general competing with ethylene for the binding site at the metal ethylene coordination is preferred over water coordination for both Ni and Pd catalyst and hydrolyzing the growing chain hydrolysis of the metal alkyl bond is competitive to ehtylene insertion.

Heterobimetallic hexanuclear cyano-bridged complexes, [{Fe(Tp)(CN)(sub 3)}(sub 4){M(MeCN)(H2O)(sub 2)}(sub 2)].10H2O.2MeCN [M = Ni (1), Co (2), Mn (3)(Tp = hydrotris(1-pyrazolyl)borate)], are synthesized in H2O-MeCN solution. Complex 1 is a canted antiferromagnet that undergoes a field-induced spin-flop-like transition, whereas 2 and 3 show antiferromagnetic intracluster coupling.

The efforts to achieve the electroreductive cyclization (ERC) and the electrohydrocyclization (EHC) reactions using nickel(II) salen as a mediator are described. While nickel(II) salen proved effective, the analogous cobalt complex as well as nickel(II) cyclam were not.

Three metal complexes, [M(super II)Cl(sub 2)(4NOPy-OMe)(sub 2)] (M = Cu, Ni, and Co) are prepared by mixing the corresponding metal chloride and 4-(N-tert-butyloxyamino)-2-(methoxymethylenyl)pyridine, 4NOPy-OMe, in 1:2 ratio. The single crystal of Co is found to have strong 2-D magnetic anisotropy in which the easy axis is the direction perpendicular to the 'ab' plane, the 'c' direction.

The X-ray structure of bis(macrocyclic-ligand) dinickel complex contains regular linear arrays of bromide-bridged, identically coordinated Ni centers at 300 K. At 100 K, the Ni complexes are displaced 20pm to form arrays of pairs of complexes with well-defined high and low-spin Ni centers.

A new family of tetranuclear Ni complexes [Ni4(ROH)4L4] (H2L = salicylidene-2-ethanolamine; R = Me or Et) were synthesized and studied. Magnetic susceptibility and inelastic neutron scattering studies indicate a combination of ferromagnetic and antiferromagnetic pairwise exchange interactions between the four Ni(super II) centers, resulting in an S = 4 spin ground state.

[Zn3.91Ni0.09(hmp)4(dmb)4Cl4] is characterized to be a single-molecule magnet (SMM) with fast quantum tunneling of its magnetization (QTM). An investigation on how the single-ion spin-Hamiltonian parameters affect the thermodynamic barrier for magnetization reversal as well as the tunnel splitting for the Ni4 single-molecule magnets (SMM) is presented.

The electronic structure of [Ni(super II)(L(sub N)(super ISQ))2] and of [Pt(super II)-(L(sub O)(super ISQ))2] is calculated by density functional theoretical and correlated ab initio methods. Electronic and resonance spectra is reported, and the electronic structures of all members of this electron-transfer series is established.

Three compounds with formula Ni{(4-C5H4N)CH(OH)-PO3}(H2O), Cd{(4-C5H4N)CH(OH)PO3}(H2O), and Gd{(4-C5H4N)CH(OH)P(OH)O2}3.6H2O are synthesized under hydrothermal conditions based on the [hydroxy(4-pyridyl)methyl]phosphonate ligand. The results of Ni{(4-C5H4N)CH(OH)-PO3}(H2O) and Gd{(4-C5H4N)CH(OH)P(OH)O2}3.6H2O revealed that weak ferromagnetic interactions are mediated between Ni(II) centers in compound Ni{(4-C5H4N)CH(OH)-PO3}(H2O).

Absorption, magnetic circular dichroism (MCD), and variable-temperature variable-field MCD (VTVH-MCD) spectroscopic techniques are employed in conjunction with density functional theory (DFT) electronic structure calculations to generate an validated description of Ni-C bonding in [Ni(tmc)CH3](super +). Spectroscopic and density functional theory (DFT) computational studies afford a quantitative bonding description for [Ni(tmc)CH3](super +) that reveals a highly covalent Ni-CH3 bond.

A dicyano-containing [Fe(bpb)(CN)2](super -) building block is employed for the synthesis of cyano-bridged heterometallic Ni(super II)-Fe(super II) complexes. The research conducted shows that the [Fe(bpb)(CN)2](super -) building block is a good candidate for the construction of low-dimensional magnetic materials.

The synthesis, structural, and magnetic features of novel oxime-bridged polynuclear complexes Ni(II) and Cu(II) are presented. Rough models are employed to fit the magnetic susceptibilities of the two antiferromagnetic complexes.

The incorporation of naphthalene molecules in the reaction solution produces three varieties of hydrothermal reaction products. These three different metal-organic framework (MOF) compounds, whose structures are made up of Ni(II), btc and bpy ligands, are synthesized.

An extensive crystallographic and spectroscopic enquiry of a complete range of the uncommon tetranuclear nickel(II) complexes is presented. The magnetic constituents of these complexes and deductions of first magneto-structural relationship for the mu4-azido connection are also reported.

A simple solution chemistry method was used to synthesize hollow spheres and thin films of Ni(OH)2 and NiO with unusual form and hierarchical structures. Ni(OH)2 hollow shells built up with nanoflakelets were obtained after subsequent removal of the core latex particles by dissolving PSA latex in toluene.

Structure and oxidation state of the Ni-Fe cofactor of the NAD-reducing soluble hydrogenase (SH) from Ralstonia eutropha were studied. Analysis of the Ni-Fe cofactor of the oxygen-insensitive NAD-reducing hydrogenase (SH) from R. eutropha by X-ray absorption spectroscopy (XAS), EPR, and FTIR spectroscopy revealed a nonstructure, (CN)(O)(sub 3)Ni(super II)(mu-CysS)(sub 2)Fe(super II)(CN)(sub 3)(CO).

A study of the chemical structure and geometrical deformations in Ni-Pd core-shell particles supported on MgO is present by X-ray photoelectron spectroscopy (XPS) and various techniques of transmission electron microscopy (TEM). It investigates the catalytic properties of the pure metal and the bimetallic particles, toward CO oxidation.

Two different types of metal phosphonates are synthesized and characterized by X-ray diffraction, magnetic measurements, IR spectroscopy, and TGA measurements. Two different types of structures are obtained and the experiments show that the manganese compound has the ability to ion exchange Cs(super +).

Black single crystals of Ni(dmit)2 complex (dmit: 2-thioxo-1, 3-dithiole-4, 5-dithiolate) with trans-4-[2-(1-ferrocenyl)-vinyl]-1-methylpyridinium chromophore as a countercation, (FcCHCHPymCH3)[Ni(dmit)2]3, were prepared by the electrocrystallization technique. Detailed crystal and electronic structure analysis reveals that the anions are stacked in the layers to form alternating dimers and monomers rather than trimers.

Three newly prepared [Ni (mnt)(sub 2)] complexes,)(HMTTF) [Ni (mnt)(sub 2)], (ChSTF) [Ni (mnt)(sub 2)], and (DBTTF (sub 2) [Ni (mnt)(sub 2)], are reported. The former two compounds have usual DA-type mixed stacks, whereas the DBTTF complexes has DDDDAA-type 6-fold columns.

The density functional method was used to optimize structures of nickel cluster ions, Ni(sub n)(super +) (n=2-8) was obtained. Compared to the reaction of a methanol molecule with Ni(sub n)(super +), it is revealed that (1) the total reaction cross section is anti-correlated to the HOMO-LUMO gap of Ni(sub n)(super +) and (2) the selectivity of the carbide formation against the demethanation is determined by a propensity, 'd-vacancy'.

The crystal structure is unique because of its organization and also because it is the first oligonucleotide crystal of B forms DNA obtained in a cubic system. This system enables designing of novel nanostructures.

A detailed theoretical study of the interaction between a central low-spin d(super 8) nickel ion and two N,N-coordinating diiminobenzosemiquinonate(1-) ligands in a square planar arrangement is reported. Geometry optimizations using various levels of density functional theory (DFT) result in excellent agreement with the experimentally determined structure and reproduce the quinoidal distortions in the aromatic rings well.

Reporting on the in-situ preparation and characterization of super conducting YBCO/CeO2 multilayer structures deposited on biaxially textured Ni alloys (RABiTS) by thermal co-evaporation is discussed. It is shows that the texture degree also depends on substrate temperature and slightly improves with increasing deposition temperature.

CeO2 buffer layers for YBCO coated conductors are deposited on biaxially textured Ni substrates by a metalorganic chemical vapor deposition (MOCVD) method using a liquid source are investigated. The variables for the texture of CeO2 films were the oxygen partial pressure (P (sub O2)), deposition temperature, and time.