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Various crystallographic studies are conducted to analyze the synthesis and the structure of the new novel linear transition metal clusters of a heptadentate bis-[beta]-diketone ligand, which reacts to give different products depending on the metal. The results have shown that the metals within these complexes weakly interact magnetically and hence lead to a suitable scaffold for the preparation of novel linear transition metals in a variety of topologies.

An efficient protocol is described for the synthesis of structurally diverse (diphenylphosphinoylmethyl)benzenes. The transformation and elaboration of 4-bromo-1,3-bis(diphenylphosphinoyl)benzene through the transition-metal-mediated procedures has produced functionalized (diphenylphosphinoylmethyl)benzenes.

B3LYP geometry optimizations are performed for the [[MN[H.sub.2]].sup.+] complexes of the first-row transition metal cations ([Sc.sup.+]-[Cu.sup.+]). The analysis of low-lying states of the amide complexes has shown different bonding pattern for the early and middle first-row transition cations ([Sc.sup.+]-[Cu.sup.+]) on one hand and the late transition metal complexes ([Ni.sup.+] and [Cu.sup.+]) on the other hand.

The density functional theory (DFT) investigation of doped fullerenes M[C.sub.59] of second- and third-row transition metals has indicated that their stability has increased toward the right-hand side of the d-block. The structural deviation of [C.sub.60] depended on the size of the metal atom while the stability is governed by electronic properties of the transition metal atom.

Large single crystals of oxygen-deficient [Sr.sub.6][Co.sub.5][O.sub.15-delta] compounds were produced using [K.sub.2]C[O.sub.3] flux in the presence of additives of transition metal oxides. The single-crystal structure determination reveals that the structures of [Sr.sub.6][Co.sub.5][O.sub.14.70] and [Sr.sub.6][Co.sub.4.9][Ni.sub.0.1][O.sub.14.36] crystallize in the space group R3 and can be described as one-dimensional face-sharing Co[O.sub.3] polyhedral chains and Sr cation chains.

C-H homocoupling of bromothiopenes and cross coupling with organostannanes was used for synthesis of oligothiophenes of well-defined structures having 2-8 thiopene units. The tolerance of carbon-bromine bond to the palladium-catalyzed C-H homocoupling leads to oligothiophenes bearing C-Br bonds at terminal thiopene rings, which allow transformation by catalysis of a transition-metal complex.

A study investigates the electronic and magnetic properties of the proposed one-dimensional transition metal, benzene sandwich polymers by means of density functional calculations. Results indicate that the 1D organometallic sandwich polymers are possible candidates for spintronic devices for spin-polarized transport since the polymers with an inherently uniform size are supposed to be also ferromagnetic (FM).

The structural and electronic properties of Ru clusters are examined and are crucial to the advancement of technology. Small, nonmetallic ruthenium (Ru(sub n)) clusters are reported to form unusual square and cubic ground-state structures within DFT by treating the exchange-correlation (XC) functional at the level of general-gradient-corrected approximation (GGA).

The formation of multilayers with polyelectrolytes and nanoscopic polyoxometalate (POM) clusters of different sizes and charges is investigated using electrostatic layer-by-layer self-assembly (ELSA). The study describes how many charges are required for irreversible adsorption and regular layer growth.

The study reports the first preparation and precise structure of monomeric transition metal cyanide. Copper(I) cyanide is a very important reagent in organic, organometallic and supramolecular chemistry.

A project which exposes students to biologically important transition-metal chemistry is illustrated by taking an example of the iron-carbonyl compound, [mu]-(1,3-Propanedithiolaro)-hexa-carbonyldiiron as a structural model for an iron-only hydro-genase. The project provides the students with experience of Schlenk line techniques, purification, and spectroscopic characterization of metal carbonyls.

The structural and magnetic properties of Mn[Fe.sub.1-x][Co.sub.x] Ge compounds with x = 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.85, 0.9, and 1.0 were investigated by means of X-ray diffraction (XRD) and magnetization measurements. XRD shows that the Mn[Fe.sub.1-x][Co.sub.x] Ge compounds crystallize in the hexagonal [Ni.sub.2] In-type crystal structure for x [less than or equal to] 0.8 and in the orthorhombic NiTiSi-type structure for [chi] > 0.8. The magnetization measurements show that the Mn[Fe.sub.1-x][Co.sub.x] Ge compounds exhibit a complex magnetic behavior. The Curie temperature increases with increasing of x. The saturation magnetization of the compounds with [Ni.sub.2] In type structure increase with increasing of x and the saturation of the magnetization in the NiTiSi-type structure also increases with increasing x. We investigated the magnetocaloric effects in these compounds by means of magnetization measurements. The maximum magnetic-entropy change observed in these compounds reaches 9 J/kgK for x = 0.8 in a field change from 0 to 5 T at around 289 K. Index Terms--Magnetic-entropy change, magnetic phase transition, transition metal compounds.

Linear muffin-tin orbital calculations were used to examine the electronic band structure of ordered equiatomic compounds of 3d transition elements (Mn, Fe, Co, Ni) with nonmagnetic 4d and 5d elements (Rh, Pd, Pt, Ir). Mn spins in a given plane prefer to align antiferromagnetically as indicated by the pronounced negative exchange interactions between four Mn-Mn first nearest pairs, J(sub 11) observed in all Mn compounds.

The article explains the structure and the magnetic properties of the different 3d transition metal wires that are grown on the vicinal Cu(111) surfaces at finite temperature.

The synthesis, characterization and bonding analyses of the closed shell 18 electron compounds [M[(ZnR).sub.n]] (M = Mo, Ru, Rh, Ni, Pd, Pt, n = 8-12), which feature covalent bonds between n one-electron organo-zinc ligands ZnR (R = Me, Et, [[eta].sup.5]-[C.sub.5][(C[H.sub.3]).sub.5] = Cp*) and the central metal M is reported. The treatment of appropriate GaCp* containing transition metal precursors could result in highly isolated 80% more yield of the compounds.

Two ternary cobaltite systems, Ba-Co-O and Ca-Co-O were utilized to understand the structures of chemically stable and nontoxic thermoelectric oxides, which exhibit a triangular network of transition-metal cations. The results obtained illustrated the physical properties like thermoelectricity or the magnetocapacitance (MC) effect related to the triangular nature of the cobalt cation lattices.

The synthesis and characterization of a series of transition metal compounds with the ligand N,N-bis(2-{pyrid-2-ylethyl})hydroxylamine is reported. The results shed light on the use of metal salts to reduce hydroxylamine that might be used as a simple method to generate N,N-bis(2-{pyrid-2-ylethyl})amine.

A systematic density functional theory computational study of the stereochemistry associated with each spin state for first transition series four-coordinate [d.sup.n] (n = 0-10) homoleptic metal complexes is described. Magic cube is used for achieving the low-spin tetrahedral structures.

The article discusses the synthesis, properties, as well as the catalytic applications of the modularly deigned transition metal neutral (PNP) and anionic (PCP) pincer ligands. These complexes can be widely used as catalysts in several important reactions, including the Suzuki-Miyaura coupling.

Tetradecker transition metal complexes containing double planar hexacoordinate carbons and double planar heptacooridnate borons are examined by using density functional theory. The results have provided a new method for synthesizing planar hyper-coordinate carbons and borons in transition metal complexes.

The correlation consistent Composite Approach (ccCA) is used for computing enthalpies of formation for a set of 17 3d transition metal species. The studies have shown that the agreement for transition metal complexes is more system dependent than in previous benchmark studies of composite methods and main group compounds.

The structural and magnetic synthesis of a series of transition-metal molecular compounds resulting from the combination of 3-pyridine sulfonate-water heterocomplexation processes is reported. The overlap between magnetic orbitals of the complexes was modified at low temperature which influenced the spin polarization mechanism along the H-bonds resulting in different intermolecular magnetic interactions.

Examples are provided to show that modified metal alkoxide precursors have an unexpected and unpredictable structural chemistry. Chemical consequences of the Lewis acidity of the metal alkoxides are discussed like adduct formation, ligand exchange reactions, or organic side reactions.

The effect of high pressures on the structural and elastic properties of [M.sub.2]GaC (M = Ti, V, Nb and Ta) is analyzed by using pseudopotential plane-waves (PP-PW) method. The structural parameters at zero-pressure are in agreement with the previous results and have also shown a linear dependence of the bulk modulus and elastic constants versus applied pressure.

The structural analysis of a hydrothermally synthesized a polyoxometalate with hybrid hexanuclear copper cluster is carried out. The spatial arrangement and magnetic properties of all the units are discussed.

The synthesis of three novel coordination polymers, [LnCu[(PZDC).sub.3].[[Ln[([H.sub.2]O).sub.9]].sub.0.5].[[[([H.sub.2]O).sub.7][H.sup.+]].sub.0.5] (Ln = La, Eu, Gd), is presented. These novel coordination polymers are the first three-dimensional (3-D)-4f heterometalic framework with supramolecular one-dimensional (1D) channels, in which lanthanide hydrate cations and lattice water molecules are located.

The electrical pulse width, pulse polarity, film thickness, resistivity distribution, temperature dependence, device impedance, and dynamic properties of [Pr.sub.0.7][Ca.sub.0.3]Mn[O.sub.3] resistance random access memory (RRAM) devices are investigated. It is inferred that Jahn-Teller effect plays a significant role in the RRAM programming property and that the rise in the resistance of RRAM devices is because of localization of valence electrons in transition metal oxide by a high density of nonequilibrium electron packet injected into the resistor from the cathode.

A study demonstrates that the n = 3 Ruddlesden (RP) phase [Sr.sub.3]La[Fe.sub.1.5][Co.sub.1.5][O.sub.10.1.sup.4] is capable of sustaining O contents as low as [O.sub.7.5] with a mean metal oxidation state of +2 and three coordination at the central site in the trilayer of originally octahedral transition metal sites. The behavior of [Sr.sub.3]La[Fe.sub.1.5][Co.sub.1.5][O.sub.10] on reduction reveals that this structure type is able to tolerate both low metal oxidation states and unusual coordination numbers.

The quasi-one dimensional electronic structures of organic charge-transfer (CT) salts rationalize Peierls transitions in mixed or segregated stacks of pi-electron donors (D) and acceptors (A). Ionic CT salts are correlated Peierls systems with a degenerate ground state (GS) at T=0 whose elementary excitations are spin solitons, while dimerized ion-radical stacks that support triplet-spin excitons have nondegenerate GS.

Conducting probe AFM is used to study several layered transition-metal dichalogenides, which in turns helps in investigating the probe-mediated thermal processes likely to arise in the probe-substrate vicinity due to the high-current densities involved. This is an illustration of a new use of conducting probe AFM to examine solid-state bulk characteristics owing to a distinctive nanoscale Joule heating.

Five Keggin-based 3D coordination polymers were synthesized and structurally characterized. Their structural differences were investigated using crystal structure analysis, which reveals that the influence of steric hindrance of organic ligand on the structures of Keggin-based coordination polymers is realized through changing the number of metal-organic units surrounding the polyoxometalate (POM) anion.

The compound [Ru(sub 2)(O(sub 2)CCF(sub 3))(sub 4)] is obtained without any exogenous ligands and crystallized by deposition from the gas phase at 170 degree Celsius. Its crystal structure is determined to confirm an infinite chain motif built on axial Ru...O interactions of the diruthenium(II,II) units.

The use of the perrhenate group to link tetracarboxylatodiruthenium(II,III) units in order to build new supramolecular structures is described. The replacement of the chloride ligand in the complexes Ru2Cl(mu-O2CR)(sub 4) by the perrhenate group results in heteropolynuclear compounds and large O-O distance in the perrhenate group prevents the replacement of the carboxylate ligands.

The view of unconventional intermolecular hydrogen bonds for organometallic complexes and transition-metal or main-group hydrides is presented. Their structures and spectroscopic manifestations are discussed and new developments in the field, especially the studies of the mechanism of proton transfer to organometallic hydrides are revealed.

A stable oxodiiron(II) complex is synthesized and characterized which contains two identical high-spin, three coordinate Fe(II) centers supported by bulky diketiminate ligands. Oxodiiron(III) complexes are very common while their reduced analogues are rare.

The first presentation of the intra- and intermolecular mechanism of C-N interconversions of transition metal alpha-cyanocarbanions is presented. The results have provided significant information on the controlled generation of N-bond alpha-cyano-carbanion active species for catalytic C-C bond forming reactions of nitriles.

A novel system is developed for encapsulating arsenic-based drugs with transition metal ions into 100-nm-scale liposomes at high density and excellent retention. These arsenic -containing lipsomes when combined with cancer cell targeting strategies would open a variety of new avenues for increasing the therapeutic index of inorganic arsenic based anticancer drugs.