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The single-electron detachment (SED) cross sections for Co- and Ir- in collision with Ar in the energy region of 10-30 keV are obtained in our laboratory. As our previous paper reported, the SED cross sections have velocity and electron affinity dependency. Using the least-squares method, we analyze the available experimental data of SED cross sections for different negative ions in collision with Ar, and get empirical formulas for different sets of anionic projectiles. For most anionic projectiles, there is a clear correlation between increasing electron affinity and decreasing SED cross sections. Co and Ir, however, are an exception, and we discuss how other physical parameters can be taken into account in the search for general scaling rules for SED cross sections. As the incident velocity increases, the cross section dependence of the anion's electron affinity becomes weaker, and the relation between the SED cross sections and [v.sub.p] is supposed to be [v.sup.1.5.sub.p]/[(2/3) + [v.sup.2.5.sub.p]]. PACS Nos.: 34.10.+X, 34.54.-s, 34.90.+q. Resume: Nous obtenons en laboratoire les sections efficaces de detachement d'un seul electron (SED) dans les collisions de Coet de Ir- sur de l'argon a des energies de 10 a 30 keV. Comme nous l'avons deja rapporte, les sections efficaces SED montrent une dependance en vitesse et en affinite electronique. Utilisant la methode des moindres carres, nous analysons les donnees experimentales sur les sections efficaces SED pour differents ions negatifs avec de l'argon et obtenons une relation empirique pour differents ensembles de projectiles anioniques. Pour la plupart des projectiles anioniques, il y a une claire correlation entre l'augmentation de l'affinite electronique et la decroissance de la section efficace SED. Cependant, le cobalt et l'iridium sont une exception et nous discutons comment d'autres parametres physiques peuvent etre pris en compte dans la recherche de regles d'echelle pour les sections efficaces SED. A mesure que la vitesse augmente, la dependance de la section efficace sur l'affinite faiblit et la relation entre la section efficace SED et [v.sub.p] est supposee etre [v.sup.1.5.sub.p]/[(2/3) + [v.sup.2.5.sub.p]]. [Traduit par la Redaction], Introduction Collision detachment is the process through which negative ions lose their electrons by collision with other atoms. Studying the collision detachment of a negative ion is significant for plasma [...]

Abstract: A detailed spectral model has been developed for the computer simulation of the 2p → 1s Kα X-ray emission from highly charged Fe ions in the electron beam ion [...]

The implantation of ZnO with dilute, radioactive [super 57][Mn.sup.+] ions has shown that Fe atoms are in a magnetically ordered atomic surrounding with ordering temperatures >>600 K. The results have challenged the concepts regarding the modeling of magnetic ordering in 3d-metal doped oxides and have shown this role of vacancies in the magnetism to be a general

The reactivity of Fe(super +) toward OCS on both quartet and sextet potential energy surfaces was investigated in this study at the B3LYP/6-311+G(d) level of theory. The studies results indicate that both the C-O and C-S bond activations proceed according to an insertion elimination mechanism would be general for the reaction of first-row transition with small sulfide molecules.

The IR spectroscopy is use to investigate the interactions of nitric oxide gas with thin layers of Fe(super ll)(TPP) and Ru(super ll)(TPP), obtained by sublimation onto low-temperature substrate (77 K). It was found that purified nitrogen oxide does not react with Fe(TPP)(NO) to give Fe(TPP)(NO)(NO2), however, this interaction led only to the formation of unstable trans-dinitrosyl complex Fe(TPP)-(NO)2.

A two-dimensional iron-nickel cyanide-bridged network at the air-water interface is formed due to the result of reaction of a Langmuir monolayer of an amphiphitic pentacyanoferrate complex with Ni2+ ions from the subphase. Characterization of these networks by different techniques was done, and it was found that air-water interface can function as a structure-directing element in the assembly of new supramolecular network solids and may help in the development of nanoscale materials.

The recent discovery of novel ferroelectricity arising from the polar ordering of [Fe.sup.3+] and [Fe.sup.2+] in a mixed valence triangular lattice oxide Lu[Fe.sub.2][O.sub.4] is discussed. Findings reveal the development of the polar superlattice of [Fe.sup.3+] and [Fe.sup.2+] below 350 K.

The studies have determined how Fe(II) substrates have accessed catalytic sites by using frog M ferritins, active and inactivated by ligand substitution, crystallized with 2.0 M Mg(II) [pulsmn] 0.1 M Co(II) for Co(II)-selective sites. The bucket brigade for Fe(II) ion access to the ferritin catalytic sites have increased the understanding of biological nanomineral synthesis and have disclosed design principles for protein cage-based catalysts and nanomaterials.

Scanning tunneling microscopy (STM) is used to image and study the [{Cp*(dppe)Fe(C[triple bond]C-)}.sub.2](1,3-[C.sub.6][H.sub.4]) both as a neutral molecule, Fe(II)-Fe(II), and as a mixed-valence complex, Fe(II)-Fe(III). The observation of charge localization in mixed-valence complexes outside of the solution environment offer new routes for the control and patterning of charge on surfaces which could find potential applications in smart materials and molecular electronic devices.

The preparation of a bis-strapped porphyrin with a pyridyl residue on one side and a malonic acid on the other side has produced after iron(II) insertion a six-coordinate complex in which both apical groups are the two axial ligands of the iron atom. The six-coordinate iron(II) complex has proved to be high-spin because of stabilization of the axial metal-ligand antibinding orbitals.

The kinetics and mechanisms involved with loading of iron(III) into iron-free ferric binding protein A (FbpA) using iron(III) citrate as an iron source in the presence of excess citrate or phosphate (physiologically available anions) at pH 6.5 is reported. The findings demonstrated the important function of FbpA as a carrier for iron chelates as well as 'naked' or free iron acquisition processes of pathogenic Neisseria gonorrheae, Neisseria meningitidis, and Haemophilus influenzae.

Correlated single-crystal spectroscopy with crystallography was employed to characterize the single crystal of the nitrite adduct of ferric myoglobin (Mb) exposed to high-intensity synchrotron X-ray radiation. The 1.55 [Angstrom] resolution crystal structure of the photoproduct reveals retention of the O-binding mode for binding of nitrite to the iron center.

The first X-ray crystal structures of [Co.sup.2+], [Fe.sup.2+] and [Mn.sup.2+] metal-substituted human histone deacetylases (HDACs), each complexed with the inhibitor M344 is reported. The results provide insight into the metal dependence of the substrate [K.sub.M] values and the [K.sub.i] values of hydroxamate inhibitors that chelate the active site metal and the affinities of metal ions that are comparable to the readily exchangeable metal concentration estimated in living cells.

The article presents a new approach for the synthesis of an iron-capped metal-organic polyyne, {[Fe][(C triple bond C).sub.2][W]triple bond C C triple bond C C triple bond [W][(C triple bond C).sub.2][Fe]}.

Mossbauer investigation is used for studying the whole cells overexpressing pyruvate formate-lyase activating enzyme (PFL-AE) following incubation under aerobic and/or anaerobic conditions and have shown that PFL-AE undergoes cluster interconversions in vivo. The studies have shown that the [[4Fe-4S].sup.2+] cluster of PFL-AE in whole cells contains a valence-localized [Fe.sup.III][Fe.sup.II] pair and the addition of adenosyl moieties to purified PFL-AE has reproduced the valence-localized state of the [[4Fe-4S].sup.2+] cluster.

Two putative nonheme iron oxygenase enzymes, KtzO and KtzP, are recombinantly expressed, characterized biochemically in vitro, and are found to stereospecifically hydroxylate the [beta]-position of glutamic acid. A method using nonhydrolyzable coenzyme A analogs is developed and used for determining the kinetic parameters for KtzO- and KtzP-catalyzed hydroxylation of glutamic acid bound to the carrier protein.

The structure of the oxide shell on Fe nanoparticles is examined by using electron energy loss spectroscopy (EELS) at the oxygen (O) K-edge with a spatial resolution of several nanometers. The results have shown that the coordination configuration in the oxide shell on Fe nanoparticles is defective when compared to that of their bulk counterparts.

The reaction of colorless iron(II) formate or the mixed-valence cluster [Fe.sub.3]O[(MeCOO).sub.6][([H.sub.2][O.sub.3]).sub.3] with formic acid in dimethylformamide exposed to air has produced black crystals of the mixed-valence ([Me.sub.2]N[H.sub.2])[[Fe.sup.II][Fe.sup.III][(HCOO).sub.6]] three-dimensional (3D) structure in which the cations have occupied half of the channels. The black crystal has appeared dark-purple when powdered and the room-temperature Mossbauer spectrum has confirmed the 1:1 ratio of Fe(II) and Fe(III).

The results of the first successful quantum chemical calculations of the Mossbauer and NMR properties in various S = 3/2 iron porphyrin complexes, covering four-, five-, and six-coordinate states and three commonly observed porphyrin conformations, such as planar, ruffled, and saddled are presented. Several interesting correlations observed among these useful experimental spectroscopic probes and geometric and electronic properties could be applied to facilitate future studies of related heme proteins and model systems.

The application of dynamic behavior of the [4Fe-4C] core for the development of redox-responsive functional molecules is demonstrated. The constructed redox-active [4Fe-4C] core could easily be incorporated into a wide variety of molecules through well-established organic reactions at the terminal alkynes.

Multipole refinement of high-resolution X-ray diffraction is used for obtaining the experimental charge densities for ([[eta].sup.5]-[C.sub.5][H.sub.5])Mn[(CO).sub.3], ([[eta].sup.6]-[C.sub.6][H.sub.6])Cr[(CO).sub.3], and (E)-{([[eta].sup.5]-[C.sub.5][H.sub.4])CF[double bond]CF([[eta].sup.5]-[C.sub.5][H.sub.4])}[([[eta].sup.5]]-[C.sub.5][H.sub.5]).sub.2][Fe.sub.2] and the resultant densities are analyzed by using quantum theory of atoms in molecules (QTAIM). Other QTAIM indicators, including the virial paths, the delocalization indices and the source function, have shown that for the n-hapto ([[eta].sup.n]-[C.sub.n][H.sub.n])M unit, there is a very similar level of chemical bonding for all M-[C.sub.ring] interactions.

A reversible gel-sol/sol-gel transition is described in poly(acrylic acid) (PAA) aqueous solutions triggered by the redox state of ferric ions conjugated with photoreduction and oxidation. The PAA solution is recovered to the homogeneous hydrogel by oxidating Fe(II) to Fe(III).

A tunable synthesis of iron nanoparticles (NPs) based on the decomposition of [{Fe[[N[(Si[Me.sub.3]).sub.2]].sub.2]}.sub.2] in the presence of organic superstructure composed of palmitic acid and hexadecylamine is described. The studies have involved an anisotropic growth process inside organic superstructures, leading to monocrystalline cubic NPs and isotropic growth outside these superstructures, yielding polycrystalline spherical NPs.