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The matrix-isolation infrared spectroscopy was used to investigate the reactions of laser-ablated La atoms with C[O.sub.2] molecules in solid argon and neon. The results revealed that the C-O stretching vibrational frequencies of OMCO decreased from Sc to La, indicating an increase in metal d orbital -> CO [pi.sup.*] back-donation in the series.

Matrix-isolation infrared spectroscopy is used to investigate the reactions of laser-ablated lanthanum and yttrium atoms with carbon monoxide molecules in solid neon. The results have revealed that the C-O stretching vibrational frequencies of MC[O.sup.+] decrease from Sc to La, thus indicating an increase in metal d orbital -> Co [pi]* back-donation in this series.

The reactions of gadolinium atoms and dimers with carbon monoxide molecules in solid argon are studied by using matrix isolation infrared absorption spectroscopy. The results have shown that besides the mononuclear gadolinium carbonyls, the dinuclear carbonyls with asymmetrically bridging and side-on-bonded CO are also formed, and they rearranged to the cyclic [Gd.sub.2]([mu]-C)([mu]-O) and [Gd.sub.2]([mu]-O)([mu]-CCO) molecules, in which the C-O triple bond is completely cleaved.

Group 11 metal carbonyls and oxides are characterized using infrared spectroscopy on the basis of isotopic substitution and CO concentration change, and density functional theory calculations. The good agreement between the experimental and calculated vibrational frequencies, relative absorption intensities, and isotopic shifts confirm the identification of the carbonyl metal oxides, and the elimination of CO2 on UV irradiation proves the oxidation of CO on group 11 metal atoms.

Reactions of laser-ablated cadmium atoms with carbon monoxide molecules in solid argon are investigated using matrix isolation infrared spectroscopy. Results reveal that the CdCO molecule is a linear triplet molecule and its formation involves Cd 5s->5p promotion.

Boron thiocarbonyl compounds BCS and B(CS)2 are studied by matrix isolation infrared absorption spectroscopy and density functional theory calculations. These boron thiocarbonyl species were produced via the reactions of CS produced by high-frequency discharge and boron atoms in solid argon matrix.

A detailed study of the reactions of silicon atoms with NO in solid argon is reported. The reaction products are identified via isotopic substitutions as well as density functional calculations.

The vibrational spectroscopic and quantum chemical calculations of the (CS2)2(super -) anion produced by condensation of high-frequency discharged CS2 in excess neon and argon are reported. Photosensitive absorptions at 909.0 cm (super -1) in neon and 908.0 cm(super -1) in argon are assigned to the antisymmetric CS2 stretching vibrational mode (b(sub 2u) of the (CS2)2(super -) anion on the basis of isotopic substitution experiments.

The study was conducted to examine the geometry and electronic structure of group 10 and 11 metal carbonyl cations,[M(CO)(sub n)](super x+) (M(super x+)=Ni(super 2+) Pd(super 2+), Pt(super 2+), Cu(super +), Ag(super +), Au(super x); n = 1-4) by the hybrid density functional method (B3LYP) and the coupled cluster method (CCSD(T)). The results reveal that the virbational frequencies V(CO) were higher by 100-165 cm(super -1) 45-115 cm(super -1) for group 11 metal complexes than that for free CO(2143 cm(super -1).

The reactions of laser-ablated yttrium and lanthanum hydrides with dinitrogen in a solid-argon matrix were performed to understand the formation of dinitrogen-hydride species of yttrium and lanthanum. The results from the infrared (IR) spectroscopy and theoretical calculations provide evidence for the formation of products HY([N.sub.2]), HYNN, [H.sub.2]YNN, HLaNN, and [H.sub.2]LaNN.

A combination of matrix-isolation infrared spectroscopy and density functional theory studies is employed to study the reactions of yttrium and lanthanum atoms with nitrous oxide in excess argon. The reactions are shown to exhibit a plausible mechanism for the formation of metal monoxide-dinitrogen and OYNN complexes.

The matrix-isolation infrared spectroscopy is employed to study the reactions taking place between the laser-ablated lathe lanthanide atoms and the dilute carbon monoxide in solid argon. The analysis of the [Ln.sub.2][[[eta.sup.2]([mu.sub.2]-C, O)].sub.x] (Ln = Tb, Dy, Ho, Er, Lu; x = 1, 2) molecules demonstrate the activation of the C-O bonds.

A combination of the matrix isolated infrared spectroscopic studies and density functional theory calculations, is employed to study the reaction of yttrium and lanthanum with dinitrogen. The reaction is shown to yield MNN, [(MN).sub.2] (M = Y and La), and [Y.sub.3]NN molecules as the products.

Matrix-isolation infrared spectroscopy is used for studying the reactions of laser-ablated yttrium and lanthanum hydrides with carbon monoxide in excess argon. Density functional theory calculations and the experimental vibrational frequencies, relative absorption intensities and isotopic shifts have supported the identification of these molecules from the matrix infrared spectra.

The reaction of metal atoms like rhodium and cobalt with carbon dioxide is investigated and a series of metal-carbondioxide complexes are experimentally characterized. Density functional theory calculations are performed on these products, which support the experimental assignments of the infrared spectra.

The reactions of laser-ablated germanium atoms with water molecules in excess argon which have was studied by using matrix-isolation infrared specroscopy is presented.

Matrix-isolation infrared spectroscopy is used to investigate the reactions of laser-ablated Cu atoms with CO and NO mixtures in solid argon and neon. The results have indicated that it is difficult for copper, silver and gold to form metal carbonyl nitrosyl complexes, while metal carbonyls and metal nitrosyls are readily formed from the reactions of metal atoms with CO/NO mixtures.

Reactions of laser-ablated silver atoms with carbon monoxide molecules in solid argon and neon are investigated using matrix-isolation IR spectroscopy. Small silver cluster carbonyls, (AgCO)(sub 2) and Ag(sub n)CO (n=2-4), as well as mononuclear silver carbonyls, Ag(CO)(sub 2) and Ag(CO)(sub 3), are generated upon sample annealing in the argon experiments and are characterized on the basis of the isotope substitution, the CO concentration change, and the comparison with theoretical predictions.

Reactions of laser-ablated zinc and cadmium atoms with carbon monoxide molecules in solid neon are examined by using matrix-isolation infrared spectroscopy. Density functional theory calculations are performed on zinc and cadmium carbonyls and the experiments have shown that zinc is more reactive with CO than cadmium.

Reactions of laser-ablated scandium and yttrium atoms with dilute carbon monoxide molecules in solid argon are investigated using matrix-isolation infrared spectroscopy. The CO activation mechanism is discussed and it stated that density functional theory calculations of the geometry structures, vibrational frequencies, and IR intensities strongly support the assignments.

The reactions of germanium atoms and small clusters with carbon monoxide molecules in solid argon are studied using matrix isolation infrared absorption spectroscopy. The results obtained indicate that Ge2CO, Ge3Co, Ge5CO are bridged-bonded carbonyl compounds, whereas Ge2(CO)2 and Ge4CO are terminal-bonded carbonyl molecules.

The laser-ablated Ag and Au atoms are reacted with high-frequency discharged Cs2 followed by condensation in excess argon at 4K. The work provides the first vibrational spectroscopic characterization of the binary Ag and Au thiocarbonyl complexes.

A reinvestigation of the reactions of ground-state boron atoms with CO in solid argon was performed. It is found that OCBBCO had a linear singlet ground-state with some boron-boron triple-bond character.

Reactions of laser-ablated early lanthanoid atoms (Ce, Pr, Nd, Sm, and Eu, except for radioactive Pm) with N 2O molecules in excess argon have been investigated using matrix-isolation infrared spectroscopy. Lanthanoid monoxide−dinitrogen complexes, OLn(N 2) (Ln = Ce, Pr, Nd, and Sm), are observed during sample deposition and identified on the basis of isotopic shifts, mixed isotopic splitting patterns, and CCl 4-doping experiments, whereas no new product is observed for Eu. The OLnNN +(Ln = Ce, Pr, Nd, and Sm) cations appear during sample deposition and increase visibly upon broadband irradiation (λ > 250 nm) at the expense of the neutral OLn(N 2) complexes. Density functional theory calculations have been performed on the new products, which support identification of the OLn(N 2) and OLnNN +complexes from the matrix infrared spectra. [ABSTRACT FROM AUTHOR]

The reactions of yttrium and lanthanum with dinitrogen were reinvestigated. Laser-ablated yttrium and lanthanum atoms were co-deposited at 4 K with dinitrogen in excess argon, and the low-temperature reactions of Y and La with N2in solid argon were studied using infrared spectroscopy. The reaction products YNN, (YN)2, LaNN, and (LaN)2were formed in the present experiments and characterized on the basis of 14N/15N isotopic shifts, mixed isotope splitting patterns, stepwise annealing, change of reagent concentration and laser energy, and comparison with theoretical predictions. Some assignments were made based on a previous report. Density functional theory calculations were performed on these systems to identify possible reaction products. The agreement between experimental and calculated vibrational frequencies, relative absorption intensities, and isotopic shifts of the MNN and (MN)2(M Y and La) molecules supports the identification of these molecules from the matrix infrared spectra. Plausible reaction mechanisms were proposed for the formation of these molecules along with tentative identification of the Y3NN molecule. [ABSTRACT FROM AUTHOR]

Reactions of laser-ablated lanthanum and yttrium atoms with carbon monoxide molecules in solid neon have been investigated using matrix-isolation infrared spectroscopy. The M(CO)xand MCO(M La, Y; x1−4) molecules have been formed and identified on the basis of isotopic shifts, mixed isotopic splitting patterns, and CCl4-doping experiments. Density functional theory calculations have been performed on these lanthanum and yttrium carbonyls. The agreement between the experimental and calculated vibrational frequencies, relative absorption intensities, and isotopic shifts substantiates the identification of these carbonyls from the matrix infrared spectrum. The present study reveals that the C−O stretching vibrational frequencies of MCOdecrease from Sc to La, which indicates an increasing in metal d orbital → CO back-donation in this series. [ABSTRACT FROM AUTHOR]

Reactions of laser-ablated silver atoms with carbon monoxide molecules in solid argon and neon have been investigated using matrix-isolation IR spectroscopy. Small silver cluster carbonyls, (AgCO)2and AgnCO (n 2−4), as well as mononuclear silver carbonyls, Ag(CO)2and Ag(CO)3, are generated upon sample annealing in the argon experiments and are characterized on the basis of the isotopic substitution, the CO concentration change, and the comparison with theoretical predictions. However, these polynuclear carbonyls are absent from the neon experiments. Density functional theory calculations have been performed on these silver carbonyls and the corresponding ligand-free silver clusters, which support the identification of these silver carbonyls from the matrix IRspectrum. A terminal CO has been found in the most stable structures of (AgCO)2, Ag2CO, Ag3CO, and Ag4CO. Furthermore, a plausible reaction mechanism has been proposed to account for the formation of the (AgCO)2and AgnCO (n 2−4) molecules. [ABSTRACT FROM AUTHOR]