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The synthesis, crystal structure, magnetic properties, and theoretical study of the 1dimensional coordination polymer [[Cu[([mu].sub.11]-[N.sub.3]).sub.2]Cu[([mu].sub.1,1]-[N.sub.3])].sub.2]Cu].sup.2} is described.

The measurements of the irreversibility field, as well as the c-axis correlated pinning in the Sm[Ba.sub.2][Cu.sub.3][O.sub.7] (SmBCO) films with high critical current densities ([J.sub.c]) are presented. The results show that the peak of [J.sub.c] decreases in a low field and then increases with the increase in the field.

The preparation of complexes of the 4-(2'-pyridyl)-1,2,3,5-dithiadiazolyl radical bidentate ligand with bis(hexafluoroacetylacetonato)-manganese(II) and with bis(hexafluoroacetylacetonato)copper(II) is presented. The spectroscopic and magnetic properties on comparison to Co(II) complex reveal that these complexes form dimers via intermolecular S..S contacts in the solid state.

Studies were conducted to determine the crystal structure and magnetic properties of P[b.sub.2]C[u.sub.3][B.sub.4][O.sub.11] which is built up from infinite zigzag chains of [[C[u.sub.3][O.sub.8]].sup.10-] units. The analysis of magnetic susceptibility and heat capacity showed that P[b.sub.2]C[u.sub.3][B.sub.4][O.sub.11] has spin-gap and Curie-Weiss behavior.

New metal-organic hybrid materials of Cu(II) are synthesized by using flexible glutarate/adipate as a bridging ligand, 2,2'-bipyridine/1,10-phenanthroline as a chelating ligand and B[F.sub.4.sup.-]/Al[O.sub.4.sup.-]/[Cl.sup.-] as a counterion. The structural analyses have shown that bridging glutarate has produced to dinuclear and tetranuclear species, whereas the adipate dianion leads to octanuclear, one-dimensional and two-dimensional polymeric complexes and the supramolecular architectures of higher dimensionality is achieved through H-bonding and [pi]-[pi] interaction.

The electrical property of grain boundaries is clarified by using the fine-grained ceramics Ca[Cu.sub.3][Ti.sub.4][O.sub.12] that are treated with the hydrofluoric acid to remove the parts of grain boundaries. The dielectric response difference between the etched samples and the pristine ones have shown that the ceramic Ca[Cu.sub.3][Ti.sub.4][O.sub.12] consists of insulating or semiconducting grains with conducting grain boundaries.

A report on very high magnetoimpedance measured at frequencies up to 1.8 GHz in nanostructured [Fe.sub.73.5][Cu.sub.1][Nb.sub.3][Si.sub.13.5][B.sub.9]/Cu film is presented. The results indicate that by playing with the sandwiched and multilayer parameter the response of a magnetoimpedance based sensor could be tuned according to the design needs.

The preparation and characterization of a series of functionalized radical anion semiquinone (SQ-Ar) ligands and their [Mn.sup.II]- and [Cu.sub.II]hydro-tris(3-cumenyl-5-methylpyrazolyl)borate complexes are reported. The results show that mesomeric substituents, Ar, would decrease the ferromagnetic contribution via direct exchange to the [M.sup.II]-SQ exchange parameters (J) for LCu(SQ-Ar) but in a series of SQ-Ar ligands, a more-withdrawing Ar would have a more ferromagnetic.

The syntheses and characterization of the crystal and magnetic structures of the mixed-anion coordination polymer Cu(HC[O.sub.2])(N[O.sub.3])(pyz) (where pyz = pyrazine) was characterized. The Cu(HC[O.sub.2])(N[O.sub.3])(pyz) undergoes a long-range magnetic ordering due to the one-dimensional Cu[(N[O.sub.3]).sub.2](pyz) and three-dimensional Cu[(HC[O.sub.2]).sub.2](pyz) compounds which display linear chain antiferromagnetism with no long-range magnetic ordering down to 2 K.

The synthesis of two new trinuclear copper(II) complexes derived from Schiff-based ligands based on the aminosugar 6-amino-6-deoxy-1,2,3-tri-O-methyl-[alpha]-D-glucopyranoside along with their structural, magnetic, and spectroscopic characterization revealing unusual properties, is described. The resulting complexes are found to display a trinuclear structure with two terminal copper-ligand moieties bridged to a central copper atom via two acetate ions and the deprotonated sugar OH groups.

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.

The relative strengths of the superexchange and super-superexchange (SSE) interactions of [Rb.sub.2][Cu.sub.2][[Mo[O.sub.4]].sub.3], Ba[Cu.sub.2][V.sub.2][O.sub.8] and K[Ba.sub.3][Ca.sub.4][Cu.sub.3][V.sub.7[[O.sub.28] by performing spin dimer analysis are evaluated. The work reveals the importance of SSE interactions mediated by the O-M-O bridges in finding the spin-lattice models relevant for magnetic oxides for [Cu.sup.2+] ions bridged by M[O.sub.4] tetrahedra.

A report is presented on the synthesis of two new derivatives of 1,4,7-triazacyclononate and their use in the preparation of 'roof-shaped' hydroxo-bridged copper(ll) complexes, in which the (Cu2(mu-OH)2)(super 2+) core is asymmetric and the two Cu-tacn moieties adopt a syn configuration across the hydroxo-bridged core. The ability of these complexes to cleave phosphate ester is examined, which has involved the study of the reaction of the complexes with the model phosphate ester, bis(nitrophenyl)phosphate (BNPP).

A new copper(II) phosphate phase, Cs2Cu3P4O14 (1) was isolated employing the mixed CsCl/2Csl molten flux, in the exploratory synthesis of compounds containing transition-metal oxide magnetic nanostructures. The synthesis, structure and the magnetic properties of the new family of copper(ll) phosphates, C(sub 2-x)Rb(sub x)Cu3P4O14 (0.0

The partial suppression of corrosion of Ag and Cu in concentrated nitric acid solution by a magnetic field up to 5 T was studied. The corrosion current density of these metals was found to diminish with magnet field and rotation speed in a rotating disk electrode experiment.

The thermal, magnetic and spectroscopic properties of the newly synthesized copper(II) complexes of 1-phenylamidino-O-alkylurea with 1,3-diaminopropane and 1,2-diaminoethane are investigated. These studies have indicated a long-range ferromagnetic exchange mediated through hydrogen bonding between copper(II) ions (S = 1/2).

The magnetic properties of all complexes were studied by variable-temperature magnetic susceptibility and magnetization measurements. The obtained parameters of J range from -33.1 to -211 cm(super -1), indicating very strong antiferromagnetic coupling between Cu(super II) ions.

The magnetic behavior of the thorium derivatives [{CuL/}(sub 2-)Th] (i = 1,2), which permitted the measurement of weak intramolecular coupling between the Cu(super II) ions in the compounds is described. This behavior of the compounds in which Th(super IV) ion is diamagnetic confirmed the presence of weak intramolecular antiferromagnetic coupling between the Cu(super II) ions.

The effects of heat treatment, magnetoannealing and postannealing of samples with induced anisotropy is presented. It is found that noncomplete inverse spinel structure was the result after annealing at higher temperature.

A series of quasimultilayers of YBa2Cu3O(sub 7-delta)(YBCO)/Y2O3 were prepared on single-crystal SrTiO3 using pulsed-laser deposition. The structural and flux pinning properties are investigated and a series of sample is explicitly compared with different Y2O3 doping contents.

The synthesis, crystal structure, and magnetic characteristics of a new crystalline polymorphic phase of tetrakis(mu2-benzoato-O,O')-bis(dimethyl sulfoxide)dicopper(II), are investigated. The results show that 1a is a molecular solid featuring structural characteristics suitable for the coexistence of both magnetic phases in the bulk material.

The ground-state electronic and magnetic properties of one of the possible structures of the trinuclear Cu(super II) site in the native intermediate (NI) of the multicopper oxidases, the mu(sub 3)-ox-bridged structure, are evaluated using the C3-symmetric Cu(sub 3)(super II) complex. The important contribution of the mu(sub 3)-oxo bridge to the ground-to-ground and ground-to-excited-state superexchange pathways that is responsible for the isotropic, antisymmetric and anisotropic exchanges are discussed.

The syntheses, structures, and magnetic properties of four polynuclear copper(II) complexes with derivatives of 1,2,4-trizole and pivalate ligands are presented. The successful isolation of 1-4 confirms that the mixed, versatile pivalate and the derivatives of 1,2,4-triazole ligands are effective in forming the nonlinear polynuclear metal complexes.

Two new phenylmalonate-bridged copper(II) complexes with the formulas [Cu(4,4'-bpy)(Phmal)]n.2nH2O and [Cu(2,4'-bpy)(Phmal)(H2O)]n is synthesized and characterized by x-ray diffraction. The conformation of the phenylmalonate-carboxylate bridge and other structural factors, such as the planarity of the exchange pathway in [Cu(4,4'-bpy)(Phmal)]n.2nH2O, account for the different nature of the magnetic interaction.

A systematic investigation of the magnetization reversal process of diamond-shaped Ni80Fe20(10 nm)/Cu(t(sub Cu) nm)/Ni80Fe20(40 nm) pseudo-spin-valve nanostructures is presented. Results reveal that the magnetization reversal process of the spin valve is strongly influenced by the Cu spacer layer thickness.

The syntheses, structures and magnetic properties of unprecedented two-dimensional (2D) layered Cu(II)-M(V) complexes [Cu(L)](sub 3n)[M(CN)(sub 8)](sub 2n).6nH2O (M = Mo (2), W (3) and L = macrocyclic ligand) with honeycomblike structures, formed by self-assembling [Cu(L)](super 2+) (1) and [M(CN)(sub 8)](super 3-) in a ratio of 3:2 are described. The temperature- and field-dependent magnetic features show that paramagnetic Cu(II) and M(V) centers are ferromagnetically and antiferromagnetically coupled through cyanide bridges.

Numerical calculations using Brandt's model are used to study the effects of phase differences between transport current and applied magnetic field on ac losses in superconductors. The effects of the phase difference (DELTA phi) on the individual components of transport loss and magnetization loss are calculated.

The speed of the magnetization switching resulting from spin transfer in pillar-shaped CoFe/Cu/CoFe spin valves and the temperature dependence thereof is studied. The demonstration of 100-ps switching validates spin-transfer switching for fast memory applications.

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.

A new quaternary layered transition-metal, Na2Cu2TeO6 is synthesized under air using stoichiometric mixtures of Na2Co3, CuO, and TeO2. The crystal structure, electronic structure, transport and magnetic properties of Na2Cu2TeO6 are presented.

A simple route to isolate the tetranuclear complex [(Cu2L)2(CO3)] is described by self-assembly of dinuclear units and adventitious carbon dioxide. The crystal structure of the complex presents some unusual features, as the miscellaneous coordination polyhedra around the metal centers.

The patterns of the Cu(super 2+)ion arrangements in the magnetic oxides A2Cu(PO4)2 (A=Ba, Sr), ACuP2O7 (Ba, Ca, Sr, Pb), CaCuGe2O6, and Cu2UO2(PO4)2 are quite different from the patterns of the strongly interacting spin exchange paths deduced from their magnetic properties. supersuperexchange interactions are found to be crucial in determining the dimensionality of magnetic properties of these magnetic oxides.

The study reports three new examples of the copper(II)-tcpd system in which two different neutral ligands are introduced as co-ligands. Compound [Cu2-(bpym)(tcpd)2(H2O)4].2H2O which involves a bridging polynitrile and a bis-chelating bpym is described as mono-dimensional chain and the use of a chelating ligand instead of the bridging bpym led to compound [Cu(tn)(tcpd)] with a 3D architecture and to compound [Cu(tn)2(tcpd).H2O with a 1D structure.

The crystal structure of isostructural SrCuV2O7 and BaCuV2O7 consists of one-dimensional (1D) zigzag chains of Cu atoms with next-nearest-neighbor interaction. The main intrachain interaction is found to be ferromagnetic and is estimated at 4.6 K.

Synthesis, structures, and magnetic properties of diphenoxo-bridged M(super II)Ln(super III) complexes derived from N, N'-ethylenebis(3-ethoxysalicyladiimine) (H2L1) are synthesized and characterized. The X-ray crystal structure determinations of 13 of these compounds reveal that they are all isostructural.

The magnetic behavior of nanocrystalline copper spinel ferrites CuxFe(3-x)O4 exhibiting different degrees of crystallinity, are investigated by means of in-field Mossbauer and dc magnetic measurements. This showed that the magnetic moments of the Fe(super 3+) ions are in a canted spin state for both the tetrahedral and octahedral sites of the spinel structure, and evidence a decrease of the average spin canting with the degree of crystallinity.

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 structural and magnetic constituents of three ladder-like coordination polymers are described along with an analysis of their spin formations. The findings reveal the effect of the character and geometry of the non-bridging ligands on the spin exchange relationship between Cu[super 2+] ions linked by the same double end-on azide bridge.

A unique and foremost example of a 2:1 cocrystal of mixed Cu(I)/Cu(II) complexes and a novel ferromagnetic bis(mu-hydroxo)dicopper(II) complex is presented. X-ray crystallographic techniques establish the composition of these complexes.

Amalgamation and structural characterization of the near perfect one-dimensional magnetic material, [BDTA]2[Cu(mnt)2] are achieved. The roughly isotropic character of the magnetic copper center and the temperature of the magnetic ordering are established by electron paramagnetic resonance (EPR) analysis.

Starting from copper hydroxy nitrate Cu2(OH3)-NO3, a series of hybrid inorganic -organic copper(II) hydroxy n-alkylsulfonate with a triangular lattice, Cu2(OH3)-(CnH(sub 2n+1)SO3)(n=6,8,10) are prepared by anion exchange. All the compounds show similar metamagnet behaviors, with a Neel temperature of about 11 K.

The synthetic peptide encompassing residues 106-126 of the human prion protein was considered for its binding properties toward copper(II), manganese(II) and zinc(II) at pH 5.7. The metal-peptide association was described by the paramagnetic effects of Cu(II) and Mn(II) upon 1D and 2D spectra, while Zn (II) was found to yield negligible effects upon any NMR parameter.

The dicynamide ligand allowed isolation and characterization of two heterodinuclear infinite chains by assembling heterrodinuclear copper-gadolinium or copper-sodium units. The presented report describes the structure of the first Cu-Gd complexes involving the dca ligands, and the Cu-Na complexes provides the first example of an unique end-on coordination of dca.

A detailed description of the magnetic behavior of heteropolynuclear complexes containing Re(IV) and an M(II) 3 metal ion (M = Cu, Ni, Mn, Fe) bridged by an oxolato ligand are reported. The compounds contain [ReCl4(ox)](super 2-) (ox = oxalate dianion) as building bloc, which exhibits different coordination modes depending on M and the auxiliary ligand used to complete its coordination sphere.

Spin-polarized electron energy loss spectroscopy is used for examining the properties of spin waves in ultrathin Co films and Fe films on Cu(001) are discussed. The spin wave excitation is observed as a well-defined peak in the loss spectrum for ultrathin Co films on Cu(001).

The effect of the magnetic field on the magnetic properties of NiFe/Cu composite wires electroplated under a longitudinal magnetic controlling field is presented. It also shifts the magnetic anisotropy of the plated layer from circumferential to longitudinal, and increases the critical frequency of the plated composite wire in magnetoimpedance effect testing, at which the magnetoimpedance ratio reaches the maximum.

The mixture and separation of the copper(I) amido complex copper (Cu) is achieved due to the reaction of [(dtbpe)Cu(Mu-Cl)]2 with LiNHPh. However, the reaction of the amido ligand of (dtbpe)Cu(NHPh) is regular in relation with the nucleophilic character.

Hybrid density functional methods and a post-Hartree-Fock approach are used to investigate the magnetic behavior of the oxo-bridged Cu(II) dinuclear complexes. Both methods confirm the strong ferromagnetic coupling predicted for such complexes at geometries close to the energy minimum.