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The study concerning isolation, characterization and molecular structure of 1,2-(Me (sub)2 S) (sub)2 B (sub)12 H (sub)10 is presented. Experiments include comparison of the properties of three (Me (sub)2 S) (sub)2 B (sub)12 H (sub)10 isomers.

The ethylidyne cluster (mu-H)3Os3(CO)9(mu3-CCH3) was synthesized by the addition of excess BH3.THF in CH2Cl2 to (mu-H)2Os3(CO)9(mu3-CCO) which involved the reduction of the unique carbonyl to a methyl group. The presence of ethylidine was also confirmed by X-ray crystal structure determination. The molecular structure of the cluster was described to be of triosmium symmetry made up of an Os3 triangle with three bounded carbonyls per Os atom. The observation was parallel with the result from an X-ray powder diffraction analysis.

Reaction between (Et3NH)2(B10H10) and CF3COOH at 60 degrees Celsius produces triethylammonium 2-(acetonitrile)nonahydro-closo-decaborate (1-). X-ray studies and 11B NMR experiments indicate the anion as (2-B10H9NCCH3)- in which CH3CN is substituted for an equatorial hydrogen on boron. Experimental data dispute the report of the formation of (1-B10H9NCCH3)- in a reaction between CH3CN and (B10H10)2-.

A simple, economic chemical vapor deposition (CVD) method for the coating of substrates with high quality homogeneous thin metal films has been developed. The physical and magnetic properties of these magnetic films have been evaluated and the results show that the film quality achieved is equivalent to those made by other techniques.

A new ambient-temperature, catalyst-free reaction between ammonia borane and tetrahydrofuran borane has produced aminodiborane by the formation of a dihydrogen bond and subsequent molecular hydrogen elimination. Aminodiborane is used for preparing an inorganic butane analogue, N[H.sub.3]B[H.sub.2]N[H.sub.2]B[H.sub.3], and its single-crystal structure has exhibited a gauche rather than an anti form conformation.

The reaction between (dimethylamino)diethylborane and 2,2'-biimidazole produced a mixture of macromolecular species of variable composition. Crystallization in the presence of moisture led to a compound with the composition C24H38B4N8O. The most probable structure of the compound was determined via X-ray analysis to consist of four boron atoms in a tetrahedral symmetry. A dihedral angle of 106.7 degrees is formed by two biimidazole planes. The B-O-B angle is 151(3) degrees and the average bond lengths are 1.605(11) Angstrom (A) for B-N, 1.607(15) A for B-C and 1.422(6) A for B-O.

X-ray analaysis, infrared and nuclear magnetic resonance spectroscopy were used to determine the crystal conformation of (C5H5N 4 Na 2 Fe2 CCO 8). The results showed that the sodium-isocarbonyl linkages formed the two-dimensional sheetlike structure. Additional studies involving the chemical behavior of the complex in dimethylformamide, tetrahydrofuran and acetonitrile were also presented.

The quantum mechanical calculation analysis was performed on a model complex, diborane-benzene cluster, which showed unusual hydrogen bonding like interaction between a borane system and benzene molecules in a molecular crystal. The results from the analysis would provide meaningful guidance for molecular engineering with diborane-benzene as a building block.

9-BBN hydroborate complexes Ti{Mu-H)(sub 2)BC8H14}(sub 3)(THF)(sub 2), Ti(Mu-H)(sub 2)(BC8H14}(sub 3)(OEt)(sub 2), and [K(OEt(sub 2)(4)]-[Ti{(Mu-H)(sub 2)BC8H14}(sub 4) were formed from the reaction of TiCl4 with K[H2BC8H14] in diethyl ether or THF. All these compounds were characterized by single-crystal X-ray diffraction analysis.

The complex Zr(9-BBN)(sub 4)[9-BBN=(mu-H)(sub 2)BC8H14}(sub 4) are synthesized via the reaction of K(9-BBN) with ZrCl(sub 4) in diethyl ether. The structure of the little compound is determined by X-ray and neutron single-crystal diffraction techniques.

Encapsulation complexes formulated as {[La(DMF)(sub 9)](sub 2)[Cu(sub 12)(CN)(sub 18)].2DMF}(sub infinity) and {[Ln(DMF)(sub 8)][Cu(sub 6)(CN)(sub 9)].2DMF}(sub infinity) were obtained from the one-step reaction of LnCl(sub 3) with CuCN and KCN in DMF. They consist of a three-dimensional Cu-CN anionic array with pockets occupied by the cation, [Ln(DMF)(sub x)](super 3+).

The divalent lanthanide 9-BBN hydroborate complexes (THF)4Ln{(mu-H)2BC8H14}2 (Ln = Eu, Yb) are synthesized by a metathesis reaction of (THF)xLnCl2 with K[H2BC8H14]. In addition, abundant studies on Ln(III) tetrahydroborates are also reported.

Two types of Lanthanide(II) (Ln(II))-Co4 isocarbonyl polymeric arrays, {(Et2O)(sub 3-x)(THF)(sub x)Ln[Co4(CO)11]}(sub infinity) and {(THF)(sub 5)Eu[Co4(CO)11]}(sub infinity), were prepared and structurally characterized. The solution structure and dynamic behavior of the [Co4(CO)11](super 2-) cluster was investigated by variable-temperature (super 59)Co and (super 13)C NMR spectroscopies.

The work on lanthanide-transition-metal (Ln-M) systems is outlined. The development of synthetic methodology for novel Ln-M compounds and the investigation for their structures is the theme of the research.

Research has been conducted on mono- and dihalogenated derivatives of (Me (sub)2 S) (sub)2 B (sub)12 H (sub)10. The synthesis of these compounds carried out from the reactions of 1,7-(Me (sub)2 S) (sub)2 B (sub)12 H (sub)10 with various halogenating reagents is described.

Results clarify previous observations on the structure and exact position of the hydrogen atom in the salts of the title anion compound. The structure reveals disorder in the crystal instead of a partially opened cage architecture. However, because of the disorderly nature of the crystals, the exact location of the 11th hydrogen atom is not ascertained.

The reduction of inner sulfonium salts, thioethers, and sulfones derived from closo-[B12H12](super 2-) by lithium in methylamine are studied. Results indicate that the reduction of inner methylsulfonium salts, thioethers, and sulfones derived from closo-[B12H12](super 2-) by lithium in methylamine produces the corresponding thiols.

The redox reaction of YbCl2 with K2[Pd(CN)4].H2O in DMF has produced a new kind of lanthanide-transition metal complex consisting of a cationic, chain-like array {[(DMF)16Yb6(mu6-O)(mu3-OH)8(mu-CN)(CN)2]6+}. The dianions [Pd(CN)4]2- link the molecular cluster [(DMF)16YB6(mu6-O)(mu3-OH)8]8+ with extra dianions [Pd(CN)4]2- serving as counterions. The structure is stable in alcoholic and aqueous solutions and in air as a solid.

Research has been conducted on the cyanide-bridged lanthanide-transition-metal arrays. The synthesis of these arrays has been carried out and the results indicate that lanthanide nitrates are strong electrolytes and that they dissociate completely in DMF solvent to form simple ions.

The quantitative synthesis of new Yb(III) inorganic arrays, ( DMF 10Yb2 Ni CN 4)3 (1) and ( DMF 10Yb2 Pt CN 4)3 (2) is achieved by reacting YbCl3 with K2M(CN)4 (M = Ni, Pt) in a 2:3 concentration, respectively. The solid state structure of 1 shows two Yb(III) ions cis connected by two Ni(CN)4(super 2-) anions. This results to lozenge-shaped Yb2Ni2 metal centers that are interconnected with Ni(CN)4(super 2-) anions, trans attached to the Yb atoms, thus generating a one-dimensional array. 2 shows the same repeating molecular units but with two inverted parallel running zigzag lines.

The 5-membered borocyclopentane ring in (eta5-C5H5)(sub 2)ZrCl (mu-H)(sub 2) BC4H8 and (eta5-C5H5)(sub 2)HfCL (mu-H)(sub 2)BC4H8 was formed by the disproportionation of the organodiborate anion H2B2(mu-H)(mu-C4H8)2- with zirconocene dichloride and with hafnocene dichloride. The rings were attached to the 16-electron metal center by hydrogen bridge systems. The two products were described to be white solids and not easily decomposed at room temperature under vacuum.

The synthesis and characterization of the complex ( eta5-C5H5 sub 2 TiB6H9)2 are presented. The complex has been prepared by the reaction of K(B6H9) with (eta5-C5H5)2TiCl in tetrahydrofuran. Spectral analysis showed that the compound is a paramagnetic dimer, and the Ti(III) is formally a 17-electron species.

11B NMR studies of the reduction of B2H6 by alkali metal naphthalides reveal the stepwise formation of two discrete, stable intermediates, (BH3)2- and (B2H6)2-, during the reduction to final products (B3H8)- and (BH4)-. IGLO calculations enable the prediction of 11B NMR chemical shifts of (BH3)2- and (B2H6)2-, and are compared with experimental data. IR and X-ray powder diffraction studies suggest the formation of a minor product, M(BH4).

The carbonyl borylidyne cluster H3OS3(CO)9 BCO, consisting of a boron atom which dons a trio of osmium atoms, is synthesized by the hydroboration of unsaturated cluster H2OS3(CO)10, the osmium-rich carbonyl group. The themolytic reaction, which, proceeded by stirring a solution of H3OS3(CO)9 BCO containing 930 milligrams of the solute and 30 ml of toluene at a temperature of 110 degree celsius for 6 days, yields a brown solid and is isolated by rotary evaporation of the solvant. An analysis of the product separated by prep thin layer chromatography (TLC) on silica using X-ray, NMR, IR and mass spectroscopy reveals the presence of HOS4(CO)12BH2 and HOS5(CO)16B, which exhibit a light yellow and reddish brown band respectively, as observed in the spectra.