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The reaction of [Ph.sub.2]P(O)(Osi[Me.sub.3]) with [([[eta].sup.5] -[C.sub.5][H.sub.5])Ti[Cl.sup.3]] or [([[eta].sup.5]-[C.sub.5][Me.sub.5])Ta[Cl.sub.4]] in dichloromethane yields the complexes [[{([[eta].sup.5]-[C.sub.5][H.sub.5])Ti[Cl.sub.2] ([mu]-[Ph.sub.2]P[O.sub.2])}.sub.2]] (1) or [[{([[eta].sup.5]-[C.sub.5][Me.sub.5])Ta[Cl.sub.3] ([mu]-[Ph.sub.2]P[O.sub.2])}.sub.2]] (2), respectively. Structural analysis of 1 and 2 by single-crystal X-ray diffraction revealed the presence of eight-membered metallacycles consisting of bridging-bidentate diphenylphosphinate groups between two metal centers. Key words: inorganic rings, phosphinate complexes, tantalum, titanium.

Some inorganic compounds have been tested as corrosion inhibitors for 6063 aluminium alloy in 3% NaCl by electrochemical and metalographic methods. The compounds were Mo[O.sup.2.sub.4], Cr[O.sup.2-.sub.4], N[O.sup.-.sub.2] oxo-anions and Li[dagger] plus and [Mg.sup.2]plus metallic cations. Results obtained show that these compounds inhibited corrosion of 6063 aluminium alloy, and that the Li[dagger] cations were the best inhibitors. The difference between pitting potential and corrosion potential increase by increasing the concentration of Li[dagger]. The maximum inhibition efficiency (E% = 85%) was attained at 5 x [10.sup.-3]M. Increasing temperature from 25 to 55[degrees]C improve corrosion resistance of 6063 aluminium alloy in the absence of Li+. However, in the presence of these cations, E% decreased at elevated temperature. Key words: corrosion, inhibition, inorganic compounds, 6063 aluminium alloy, 3% NaCl.

Analysis of the solid-state powder [sup.59]Co NMR spectra of ten simple inorganic cobalt(III) complexes at 11.75, and in most cases, 4.7 T have permitted the assignment of specific ligand planes to ranges of values of the observed chemical shift principal components. The relevant chemical shift components were determined from the simulations of the powder line shapes. These simulations also provided the relative orientations of the chemical shift (CS) and electric field gradient (efg) tensors, as well as magnitude and asymmetry of the [sup.59]Co quadrupolar coupling. Using symmetry arguments and ab initio calculations, as appropriate or necessary, the orientations of the efg tensors in the molecular frame were deduced. This allowed the determination of the CS tensors in the molecular frame and thus assignment of the ligand planes responsible for the observed values of chemical shifts. Key words: cobalt, chemical shift, quadrupolar coupling, solid state NMR.

The hydrosilylation reaction of phenylacetylene, generated on the surface of solid catalysts (such as Pt and Ru) supported on inorganic matrices such as MgO obtained by the sol-gel process, yields vinylsilanes as the main products. The products' distribution, specific activity, and turnover reactions were determined for the case of the hydrosilylation reaction of PhC[equivalent]CH with [R.sub.3]SiH (R = [Ph.sub.3], [Ph.sub.2]Me, and Ph[Me.sub.2]). For [Ph.sub.3]SiH and [Ph.sub.2]MeSiH, the presence of [beta]-trans and [alpha] isomers is observed. Addition of Ph[Me.sub.2] SiH to phenylacetylene leads to the formation of [beta] (cis and trans) and [alpha] isomers. These catalytic systems provide a new synthetic route to Si--C. Key words: vinylsilanes, cataleseur sol-gel, hydrosilylation et phenylacetylene.

Cluster compounds represent an important class of molecules that lie between the bulk metal and conventional chemistry based on single metal centres. They contain three to 150 metal atoms bonded together by covalent bonds in a polyhedral arrangement that does not necessarily conform to that found in the bulk metal. Their electronic structure has been interpreted using free-electron spherical harmonic models that relate the polyhedral features to the total number of valence electrons in the molecule. The occurrence of these molecules raises interesting questions regarding the transition from metallic to non-metallic properties.

Research has been conducted on molecules containing only nitrogen atoms. The authors have investigated N (sub)12 cages with single bonds via the use of theoretical calculations in the effort to determine which of the cages is the most thermodynamically stable.

Research has been conducted on manganese(II) complexes. The authors describe the isolation of these complexes from Mn(ClO (sub)4) (sub)2 or Mn(acac) (sub)2 solutions, and report that the structure of the complexes has been determined via the use of X-ray crystallography.

Research has been conducted on one-dimensional nanostructures. The authors report that the short-chain polymers promote 1D ZnO nanostructure formation.

Research has been conducted on europium(II) metallopeptides which have been designed on the basis of helix-turn-helix structure and EF-hand motifs. The study of these metallopeptides carried out via the use of europium(II) excitation spectroscopy is discussed.

Research has been conducted on bis(di-mu-ethoxo-bis(3,5-di-tert-butylsemiquinonato)dicopper(II)) complex. The authors describe the synthesis of this complex and its structure which has been determined via the use of single-crystal X-ray diffraction.

Research has been conducted on copper complexes. The authors have investigated the effects of ligands on the redox activities and structure of these complexes via the use of (2-pyridyl)alkylamine derivatives as supporting ligands.

Research has been conducted on crystalline stibnite rod bundles of straw. The synthesis of these bundles has been carried out by wet chemical method via thermal decomposition of antimony(III) diethyldithiocarbamate complex in ethylene glycol under mild conditions.

Research has been conducted on inorganic linear polymer which consists of Mn(II) and N-centered tripodal ligand. The crystal structure and magnetic properties of this polymer have been investigated and discussed.

Research has been conducted on polyoxometalates. The preparation of these compounds in aqueous solution, and their characterization via elemental analyses are described.

Research has been conducted on guanidium ion (NH (sub)2) (sub)3 C (super)+ complexes containing super Lewis acidic BH (sub)4 (super)+ and AlH (sub)4 (super)+. The authors report that the structures of these complexes have been calculated via the use of density functional theory method.

Research has been conducted on ruthenium-thiopyrimidine complexes. The authors discuss the crystal and molecular structures of these complexes, the molecular modeling analysis of the molecules, and the spectrophotometric, redox and cytoxic properties of these molecules.

Research has been conducted on alkylaromatic compounds. The study of the oxidation of these compounds in CH (sub)3 CN by trans-dioxoruthenium(VI) complex is presented.

Research has been conducted on Cl (sub)3 B-NH (sub)3 and F (sub)3 B-NH (sub)3 complexes. The authors have calculated bond dissociation energies and geometries of these complexes via the use of density functional theory, and they report that the calculations show a larger bond dissociation energy for Cl (sub)3 B-NH (sub)3 than for F (sub)3 B-NH (sub)3.

Research has been conducted on water-soluble anionic silver 2-mercaptonicotinate complex which possesses antifungal and antibacterial properties. The authors describe the synthesis of this complex.

The authors discuss electrostatic minimum potential (V (sub)min). The hypothesis that this potential could be used as a quantitative measure of the sigma donating power of substituted phosphorus(III) ligands has been tested, and the results are reported.

Research has been conducted on carboxy-substituted alkylammonium salt. The preparation of this salt and its use as incoming carboxylate ligand in a ligand-exchange reaction to produce Mn (sub)12 single-molecule magnet are described.

Research has been conducted on titanium(IV) imide. The authors describe the reaction of this compound with ketene OCCPh (sub)2 which produces tripodal diimine complex.

Research has been conducted on heptadentate ligand tris[6-((2-N,N-diethylcarbamoyl)pyridyl)methyl]amine. The authors describe the synthesis of this ligand which has pyridinecarboxamide arms connected to central nitrogen.

Research has been conducted on Re (transforms to) MQ (super)+ MLCT excited state of [Re(MQ (super)+)(CO) (sub)3 (dmb)] (super)2+, where MQ (super)+ is N-methyl-4,4'-bipyridinium, and dmb is 4,4'-dimethyl-2,2'-bipyridine. The characterization of this excited state via picosecond time-resolved IR and resonance Raman spectroscopy is described.

Research has been conducted on bisperoxovanadium(V) compounds with bidentate ligands. The authors report that these compounds inhibit tumor growth via cleaving DNA, and they describe the mechanisms and kinetics of ligand substitution reactions of bisperoxovanadium(V) compounds with entering picolinic and dipicolinic acid ligands at physiological pH.

Research has been conducted on homoleptic metal amidinates. The authors describe the preparation and structural characterization of these compounds carried out for the transition metals Ti, Mn, V, Co, Fe, Ni, Cu, La and Ag.

Research has been conducted on intermetallic aluminum silicides which have been produced via the reactions carried out in aluminum flux. The authors have determined the structure of these compounds by means of single-crystal X-ray diffraction.

Research has been conducted on chlorine dioxide. The authors describe the reaction of this compound with nitrogen dioxide carried out via stopped-flow spectroscopy in the presence of ClO (sub)2 (super)- in order to produce ClO (sub)2 (super)- and NO (sub)3 (super)-.

Research has been conducted on nickel borohydride complex. The authors report that this complex has been prepared via the use of nitrogen-donor ligand hydrotris(3,5-dimethylpyrazolyl)borate.

Research has been conducted on tris(2-pyridylmethyl)amine ligands. The authors described the stereocontrolled synthesis of these compounds as potential ligands of lanthanide cations.

Research has been conducted on nanocrystalline TiO (sub)2 sensitized with cis-bis(4-carboxy-2-[2'-(4'-carboxypyridyl)]quinoline)bis(thiocyanato-N)ruthenium(II) complex. The authors have investigated the electrochemical, photoelectrochemical and spectral properties of this nanocrystalline, and compared these properties with those of the other complex.

Research has been conducted on acetonitrile solutions. The authors have investigated the photophysical properties of these solutions, and have described the results.

Research has been conducted on isomeric binuclear ligands and their copper(II) complexes. The authors describe the preparation of these complexes and ligands, and discuss their use for hydrolysis of a phosphodiester substrate bis(p-nitrophenyl)phosphate.

Research has been conducted on cation-deficient Ruddlesden-Popper oxysulfide Y (sub)2 Ti (sub)2 O (sub)5 S (sub)2. The authors report that potassium intercalation into this compound has been carried out via the reaction between oxysulfide and potassium vapor in sealed metal tubes in order to produce KY (sub)2 Ti (sub)2 O (sub)5 S (sub)2.

Research has been conducted on mono- and dinuclear complexes of ruthenium carbonyl. The authors describe the preparation of these complexes, and report that the complexes have trans,cis-{Ru(PR (sub)3) (sub)2 (CO) (sub)2} units.

Research has been conducted on oxo ligands. The authors have investigated oxo ligands' nucleophilic reactivity in the groups M (super)VI O (sub)3 of the trigonal complexes, and they report the results.

Research has been conducted on silver(I) double salts containing 4-hydroxyquinoline ligand. The authors describe the synthesis of these salts carried out via the hydrothermal method.

Research has been conducted on dinuclear hydroxo complex cis-[L (sub)2 Pt(ONO (sub)2){9-MeAd(-H)}PtL (sub)2](NO (sub)3) (sub)2, where L is PMePh (sub)2. The authors have demonstrated that this complex deprotonates NH (sub)2 group of 9-methyladenine in solution to produce cis-[L (sub)2 Pt{9-MeAd(-H)}] (sub)3 (NO (sub)3) (sub)3.

Research has been conducted on platinum(II) biphenyl dicarbonyl complex. The authors have investigated and discussed the excited-state properties of this complex in the effort to understand the aggregation process in concentrated solutions.

Research has been conducted on silver-antimony sulfides. The authors report that these compounds have been prepared solvothermally in the presence of ethylenediamine, and have been characterized via thermogravimetry, elemental analysis and single-crystal X-ray diffraction.

Research has been conducted on chelating dianionic [ONNO]-type amine bis(phenolate) ligand. The authors report that the reaction between this ligand and VO(OR) (sub)3, where R is (super)i Pr, (super)i Bu, CH (sub)2 CF (sub)3, produces isomer mixture.

Research has been conducted on homometallic complexes with several ruthenium polypyridyl units linked by amino acid lysine and dipeptide. The synthesis, spectroscopic, electrochemical and electrochemiluminescence properties of these complexes have been investigated and described.

Research has been conducted on monoclinic jamesonite, (FePb (sub)4 Sb (sub)6 S (sub)14). The authors describe the synthesis of this compound carried out via the elements' direct reaction under dry conditions with sealed evacuated tubes.

Research has been conducted on double metal cyanide derivatives of zinc(II) and iron(II). The sythesis of these derivatives and their preparation are described.

Research has been conducted on preformed hexanuclear and tetranuclear iron(III) clusters. The authors describe the use of the clusters' alcoholysis for the synthesis of higher-nuclearity clusters.

Research has been conducted on iron complexes which include polyimidazole and exchangeable ligands. The authors have investigated these complexes in order to model the structural and functional features of dinuclear proteins' non-heme iron centers.

Research has been conducted on binary compound Sr (sub)3 In (sub)11. The authors describe the synthesis and structural characterization of this compound carried out via X-ray diffraction experiments.

Research has been conducted on vanadium carbide, titanium carbide and titanium nitride. The authors report the use of density functional theory calculations on high-symmetry stoichiometric clusters in order to model the surface electronic structure and bonding properties of these compounds.

Research has been conducted on bifunctional ligands which are P,O derivatives. The authors report that the Z stereochemistry makes these ligands act as P,O-chelates.

Research has been conducted on quaternary vanadium niobium compounds which have triangular Nb (sub)3 clusters. The authors describe the preparation of these compounds in sealed tubes from stoichiometric amounts of ACl, where A is K, Rb, Cs, Tl, or Tl metal.