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A quantum mechanical analysis of acetonitrile, formamide and their equimolar mixture is conducted to study the structure of different liquids. The results prove that the liquids can be easily modeled like a shell system with solvated clusters.

The rate of the nucleophilic substitution reaction of tributylamine with methyl p-nitrobenzenesulfonate was analyzed to gain better understanding of measures of bulk and local polarity in C[O.sub.2]-expanded acetonitrile. The results showed that reaction kinetics are significantly influenced by local composition enhancement in C[O.sub.2]-expanded acetonitrile.

Multivariate Raman curve resolution is used for studying vibrational spectroscopic features associated with perturbations of solvent molecules by various solutes. The results have shown new OH stretch bands arising from water molecules associated with polar solutes.

The development of new method to synthesize perfluoro[2.2]paracyclophane from reaction of 1,4-bis(chlorodifluoromethyl)-2,3,5,6-tetrafluorobenzene with Zn, heated in acetonitrile at 100 degree Celsius is reported. The study demonstrates the application of Perfluoro[2.2]paracyclophane for deposition experiments to determine the impact of perfluorination on properties of the respective parylene polymer.

A new two-dimensional classification of singlet carbenes is described that is based on the difference in reactivity of their insertion reactions into the C-H bonds of acetonitrile and isobutene. Strong hydrogen bridging is observed between a C-H bond of acetonitrile and the nucleophilic carbenes.

The complex [[Ru(bpy)[(AN).sub.4]].sup.2+] (bpy = 2,2'-bipyridyl, AN = acetonitrile) has undergone a very clean photoreaction yielding only trans-[[Ru(bpy)[(AN).sub.2][(solv).sub.2]].sup.2+] when irradiated with visible light in an adequate solvent. The two-step photoreaction has provided a quantitative path for preparing trans-polypyridine species with interesting photochemical reactions.

The studies related to the reduction and solution speciation in acetonitrile of two mononuclear Ru complexes containing the redox-active 9,11,22-tetraazatetrapyridopentacene (tatpp) ligand is presented. The studies provide insight into concentration dependent redox chemistry of planar aromatic structure of the tatpp ligand and formation of new covalent bonds between complexes during the reduction.

Picosecond fluorescence experiments are used for examining the intramolecular charge transfer (ICT) reaction of 1-tert-butyl-6-cyano-1,2,3,4-tetrahydroquinoline (NTC6) in n-hexane and acetonitrile (MeCN). The decay of the locally excited (LE) absorption and the growing-in for the ICT state of NTC6 have shown that the ICT state has originated from the LE precursor and is not formed by direct excitation from [S.sub.0].

An acetonitrile solution of mercury(II) chloride found to catalyze efficiently the conversion of a diverse range of ketoximes into their corresponding amides/lactams. It efficiently catalyzes the rearrangement of a variety of acyclic and cyclic ketoximes with good to excellent yields under neutral condition.

The addition of alcohol group to nitrile molecules is achieved in presence of metal cluster. It gives rise to cluster complexes with imino ester ligands.

The electrostatic interactions in liquid acetonitrile are described using a discrete model based on the multipolar expansion including terms up to hexadecapoles. It is found that the permanent local field is dominated by the dipole-dipole interactions although the contribution of the higher multipoles is not negligible for accurate predictions.

Essentially solvent-free [[Cp*Ir[Cl.sub.2]].sub.2] catalyzed redox neutral processes are reported, where substituted acetonitriles react with primary alcohols to deliver monosubstituted aryl/heteroaryl acetonitriles in excellent yield. The experiments have demonstrated that these processes can be achieved by conventional or microwave heating and that bis- and tris-primary alcohol can also be processed efficiently.

The kinetics, thermodynamics, and the reaction intermediate are studied for the reaction of NADH analogue 1-(p-substituted benzyl)-1,4-dihydronicotinamide (G-BNAH) with the radical cation of N-benzylphenothiazine (PT[Z.sup.+]) in acetonitrile. A significant negative kinetic temperature effect is observed on the hydride transfer from BNAH to PT[z.sup.+].

Reduction or oxidation of molecules is an elementary step in many chemical processes and the redox potentials of many compounds are known experimentally and provide a direct measure of the free energy cost of adding or removing electrons from a species and thus of their relative stability. Redox energies are the condensed-phase equivalents of the electron affinities and ionization potentials in the gas phase, with the pressure of the solvent playing a crucial role.

Steady-state and time-resolved X-ray absorption spectroscopy (XAS) is performed on the iron K-edge of [Fe(tren(py)3)](PF6)2 dissolved in acetonitrile solution. Static XAS measurements on the low-spin parent compound and its high-spin analogue, [Fe(tren(6-Me-py)3)](PF6)2, reveal distinct spectroscopic signatures for the two spin states in the X-ray absorption fine structure.

The photophysics of the binuclear tetraazatetrapyridopentacene complexes was studied in acetonitrile and dichloromethane by fematosecond and nanosecond time-resolved techniques. It was found that with the aromatic tatpp bridging ligand, complexes of Ru(II) and Os(II) have different types of lowest triplet excited state, ligand-centered in the case of Ru(II) and metal-to-ligand charge transfer in the case of Os(II).

A hybrid quatic force field with quartic force constants calculated at the CCSD(T)/cc-pVTZ level and cubic and quartic terms determined by a B3LTP/cc-pVTZ treatment is proposed to compute the vibrational energy levels of acetonitrile from a variational method. Fundamentals and overtones calculated in the range of 300-3200cm(super -1) are in fair agreement with the observed data, with an absolute mean deviation of less than 0.8%.

The interconversion of CH3CN(super +.) and its lower energy isomer CH2CNH(super +.) by calculation, collision-induced dissociation mass spectrometry and ion-molecule reaction is demonstrated. The latter ion, ionized ketenimine, is co-generated upon electron or chemical ionization of neutral acetonitrile in the ion source of a mass spectrometer.

The effect of the long-range part of Coulombic interactions on properties of complex polar and association fluids and has detailed three compounds with extreme features is studied. The results confirm with the earlier findings that the properties of polar and associating systems are determined by the short range interaction regardless of their nature and contributions that rise from the long range interaction that constitute only a small portion of the total properties.

A picosecond Kerr-gated time-resolved resonance Raman examination of the 2-fluorenylnitrene and 4-methoxyphenylnitrene reactions with water to form the singlet 2-fluorenylnitrenium and 4-methoxyphenyl-nitrenium ions is presented. Photolysis of 2-fluorenyl azide and 4-methoxyphenyl azide in mixed water/acetonitrile solvents led to the formation of transient species within a few picoseconds.

It is stated that, azobis(isobutyronitrile)- initiated autoxidation of gama-terpinene in acetonitrile, yields p-cymene and hydrogen peroxide(1:1), in a chain reaction carried by the hydroperoxyl radical.

Mixtures of CH3CN and H2O are the predominant solvent systems used in reversed-phase liquid chromatographic (RPLC) separations. The present data support the existence of a microheterogenous solvent structure that varies continuously over the full range of temperatures and compositions examined.

The differences in water and acetonitrile structures in a binary system due to local compositional dissimilarities are examined through molecular dynamic simulations. The results for the acetonitrile group structures are found to be consistent with the experimental data of binary acetonitrile/water mixtures.