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The Fe(II)-N[O.sup.+] ground state of six-coordinate ferric heme nitrosyls is characterized by using the model complex [Fe(TPP)(MI)(NO)](B[F.sub.4]) (MI = 1-methylimidazole). The potential energy surface (PES) calculations have disclosed a complex energy landscape for binding of NO to ferric heme.

The nature of the Fe-[O.sub.2] bonding in oxy-myoglobin is examined by hybrid quantum mechanical/molecular mechanical calculations and gas-phase calculations using density functional theory (DFT). The protein has strengthened the [Fe.sup.III]-[O.sub.2.sup.-] character of the complex, thus affecting its bonding features and the oxygen binding affinity of Mb.

A hydrophilic/lipophilic bias is used for inducing a favorable arrangement of potentially spin-labile iron(III) centers. Careful chemical modulation is required for the control and improvement of cooperativity of spin-labile iron(III) complex in solution.

A 1.4 Angstrom resolution crystal structure of the [Fe.sup.2+]-dependent enzyme cysteine dioxygenase (CDO) containing putative intermediate persulfenate trapped in its active site pocket is reported. The results revealed that the Fe-proximal oxygen atom might be involved in the primary oxidation event to give a unique three-membered Fe-S-O cyclic intermediate and facilitate isomerization of the persulfenate to the sulfinate product.

The fate of the iron complex nitrilotriacetic acid-Fe(III) (FeNTA) is examined during the photo- and biodegradation processes. The results have proposed mechanistic schemes for FeNTA degradation by solar light and by Rhodococcus rhodochrous.

A ferrofluid composed of [gamma]-[Fe.sub.2][O.sub.3] nanoparticles dispersed in n-decane are prepared and a series of magnetic measurements are carried out on samples frozen in a magnetic field and in zero magnetic fields. The effect of interparticle interactions on the magnetic behavior of ferrofluids is studied and the potential use of magnetic measurements in estimating the extent of nanoparticle fusion into clusters behaving as superspins is discussed.

The aqueous two-phase systems formed by adding poly(ethylene oxide) to an aqueous salt solution are used to study the partitioning behavior of pentacyanonitrosilmetallate complexes. The results showed that the presence of anions in the polymer-rich phase is caused by an EO-[[M[(CN).sub.5]NO].sup.x-] (M = Fe, Mn, or Cr) enthalpic interaction.

A rare family of five and six-coordinated high-spin Fe(III) porphyrins incorporating weak axial ligands are prepared and characterized, which has shown stepwise metal displacements in a single distorted macrocyclic environment. The large anodic shifts have shown the effective removal of the metal-centered electron density by the macrocycle when the metal is constrained to reside in the porphyrin plane.

The dual-energy doses were used to optimize the [Fe.sup.+] ion-damaged InP materials for photoconductive detector (PCDs) signal to noise performance. The data obtained in combination with a deconvolution algorithm provide an excellent spectral response correction to the raw photocurrent signal recorded by the PCDs.

A combination of Rutherford backscattering/channeling spectrometry and time-of-flight elastic recoil detection analysis is used to study the undoped wurtzite GaN epilayers implanted at room temperature with 50-325 keV [Fe.sup.+] ions. The results showed that both radiation enhanced diffusion and the thermal diffusion of Fe atoms near the surface should be at least five times larger than ordinary bulk diffusion in order to explain the increased Fe surface concentration.

The magnetization measurement and [super 57]Fe Mossbauer spectroscopy was employed to study the origins of various valence states of various Fe ions above the 3+ state for 30% Fe-substituted [Li.sub.2]Mn[O.sub.3] with a layered rock-salt structure.

The thermal stability and corrosion resistance of the magnetic anisotropy of surface-step atoms in nanopattenred ultrathin Fe/Ag(001) films are analyzed. Capping the nanopatterned films with ultrathin chromium overlayers allowed preserving the magnetic anisotropy due to step atoms while extending its thermal stability to above 670 K and greatly enhancing its resistance under oxidizing atmospheric environment.

A simple undergraduate physical chemistry laboratory course to introduce students to kinetics and mechanism of iodide oxidation by iron(III) ions in an acidic medium is described. The students gain insight into the reaction mechanism and the dependence of reaction rate on reactant concentration.

Synthesis and characterization of monomeric [Fe.sup.III]OH complexes with trigonal-bipyramidal primary coordination spheres is discussed. Three anionic nitrogen donors define the trigonal plane, and the hydroxo oxygen atom is trans to an apical amine nitrogen atom.

Ab initio calculations have helped in constructing an n-body Fe-Nb embedded-atom potential and are used for studying the crystal-to-amorphous phase transition through molecular dynamic simulations. The formation mechanism of the metastable phases and the fractal pattern observed in the Fe-Nb system are discussed in terms of the atomic collision theory and the well-known cluster-diffusion-limited-aggregation model.

The synthesis, detailed characterization, and ligand binding properties of iron complexes of tetraanthracenotetraazaporphyrin (TATAP) is reported. The binding affinity of Fe(TATAP) to THF, a variety of neutral nitrogenous axial ligands, and carbon monoxide is explained based on an unusual positive iron(III/II) redox potential when coordinated by the TATAP ligand.

A first-principles calculations that models the effect of iron (Fe) atoms on the adsorption of a tungsten (W) atom on W(100) surfaces is reported. The results provide insight into fundamental mechanism that activated sintering of tungsten by Fe atoms.

The article explains the enhanced hall effect, which is observed in the [Fe.sub.x][Ge.sub.1-x] nanocomposite films that are composed of nanoscale Fe grains embedded in amorphous Ge matrix. An increase in the Fe atomic fraction x is shown to change the transport mechanism of the films from a semiconducting to metallic character.

The electronic structure and zone-center phonon modes in bulk BiFe[O.sub.3] with rhombohedral R3C symmetry are examined. The electronic structure results are used for determining the zone-center phonon modes by applying a linear response technique.

The uptake of nontoxic magnetic nanoparticles (MNPs) by cancer cells is examined. The studies have shown that the MNPs do not require additional transfection agent, which has provided a cost effective means of treatment with significantly lower dosage in the body in comparison to commercially available nanoparticles.

A comparative study was conducted to determine the influence of different interatomic potentials on the formation of the He-vacancy clusters within displacement cascades in [alpha]-Fe. The differences observed in postcascade He-V configuration can be attributed to the differences in the Fe-Fe and Fe-He potentials.

The iron 2p and carbon 1s near-edge X-ray absorption fine structure (NEXAFS) spectra of substituted ferrocene compounds are interpreted with the help of extended Huckel molecular orbital (EHMO) theory and density functional theory (DFT). The substituent effects are related to the electron donating/withdrawing properties of the cyclopentadienyl ligands and their substituents as well as the presence of [pi]* conjugation between the cyclopentadienyl ligand and unsaturated substituents.

The synthesis and characterization of two new [N.sub.4][O.sub.2]-coordinated spin crossover iron complexes with cooperative spin transitions are described.

Thermal deposition (TD) and pulsed laser deposition (PLD) methods are used for preparing GaAs/Fe(001) crystalline ultrathin films. The effective perpendicular demagnetizing fields in the PLD films have decreased when compared to the TD samples because of an increase in the interface uniaxial perpendicular anisotropy at the Fe/Au(001) interface.

Spin-wave excitations in ultrathin epitaxial FeCo(001) films on Au(001) with in-plane magnetic anisotropies drastically reduced in comparison to pure Fe(001) films. The results reveal that the effect of a weak in-plane anisotropy is overcompensated by the enhanced exchange interaction.

The study was conducted to measure the spatial distribution of the velocity distribution functions of Fe atoms in a dc magnetron sputtering plasma source by Doppler-shifted laser-induced fluorescence imaging spectroscopy. These results represents the relaxation process of the energy of sputtered Fe atoms and during the transport toward the downstream plasma, the energy of Fe atoms is reduced and the velocity distribution function is thermalized by collision with ambient Ar gas.

Atomic and magnetic force microscopy measurements on magnetic iron particles produced by a self-assembly method is presented. Magnetic force microscopy suggests that the particles can be permanently magnetized with external fields of different orientations.

The electronic structure and the Fe moment distribution in Nd(sub 5)Fe(sub 17) are calculated using the first-principles orthogonalized linear combination of atomic orbitals method. The total magnetic moment and the average Fe moment are in good agreement with experimental measurements.