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The pump-probe photoionization of isolated benzonitrile (BN) and phenylacetylene (PA) in a supersonic beam is discussed. Results suggest the production of a low-ionization-potential species, which lasts more than hundreds of microseconds after excitation to the [S.sub.1] states.

The specific rotations of several substituted oxiranes, 2-chloropropionitrile and 30 degree-rotated ethane are calculated by using a sum-over-states approach. The first few excited states proved to have only a relatively small effect on the calculated specific rotation, in each case, and hence the need to use a large number of excited states was observed, in order to achieve convergence wit the results of the more direct linear response method.

The isomerization and decomposition of 1,2-benzisoxazole are analyzed behind reflected shock waves in a pressurized driver, single-pulse shock tube. The rate constants are estimated on the basis of the potential energy surfaces by using transition-state theory and are compared to the experimental results obtained by the single-pulse shock-tube method.

The generation of gas-phase vanadyl (V[O.sup.2+]), vanadyl hydroxide (VOO[H.sup.+]) and vanadium(V) dioxo (V[O.sub.2.sup.+]) cations complexed with nitrile ligands by using electrospray ionization (ESI) is described. The results have shown that the [[V[O.sub.2][(L).sub.2]].sup.+] species requires higher collision energies to liberate the nitrile ligand, indicating that they are strongly bound than the [[VOOH[(L).sub.2]].sup.+] counterparts.

The electric deflections of p- and m-aminobenzonitrile (PABM and MABN) and of p- and m-(dimethylamino)benzonitrile (PDMABN and MDMABN) molecules are presented. The change in symmetry and the introduction of methyl groups have led to a transition from the rigid response to the linear response.

The charge transfer (CT) state formation of trans-4-dimethylamino,4'-cyanostilbene (DCS) is examined in a solvent using ab initio complete active space self-consistent field calculations combined with polarized continuum model. The DCS as well as 4-dimethylaminobenzonitrile studies confirms that skeletal relaxation where the benzene ring loses its aromaticity is essential to stabilize the CT state in a solvent besides the torsional motion.

Coupled-cluster and density functional methods are used to determine specific rotations and electronic circular dichroism (ECD) rotational strengths for (S)-2-chloropropionitrile. Density functional specific rotations using the B3LYP functional with basis sets of quadruple-zeta quality containing up to 588 functions are found to be too large compared to experiment by almost a factor of 2.

The mechanism of the protonation of the rhenium nitrile chloro-complexes, taken as a model of the real systems leading to the azavinylidene products is investigated. The result shows that the cis-isomer of 2, the initially formed cholro-protonated species further converts to the azavinylidene cis-3 via either an acid-independent 1,4-proton shift or an acid-base catalyzed pathway involving a second protonation of the nitrile carbon atom.

Condensed-phase effects on the structure and bonding of C6H5CN-BF3 and (CH3)3CCN-BF3 are illustrated by a variety of results, and these are compared to analogous data for the closely related complex CH3CN-BF3. The result shows that the condensed-phase effects on the structural properties of C6H5CN-BF3 and (CH3)3CCN-BF3 are much less pronounced than those for CH3CN-BF3.

Excitation-energy dependence of fluorescence intensity and fluorescence lifetime is measured for 4-dimethylaminobnzonitrile (DMABN), 4-aminobenzonitrile (ABN), 4-diisopropylaminobenzonitrile (DIABN), and 1-naphthonitrile (NN). Results indicate that the strong decrease in the relative fluorescence yield at higher energies is due mostly to a decrease in the radiative decay rate of the emitting state.

The kinetics of oxidation of nitrile to nitrate by peroxynitrous acid at 5.2 can be described by the rate law K(sub obs) =k(sub iso) + K'[NO2(super -)] + k'[NO(sub 2)(super -)](super 2), in which the peroxynitrous acid isomerization rate constant K(sub iso) = (1.10 plus or minus 0.05)s(super -1), K'=(3.2 plusmn 0.1) M(super -1) s(super -1), and K'=(4.2 plusmn 0.3) M(super -2)s(super -1), at 25 degree Celsius.

The excited state intramolecular charge transfer reaction of 4-(1-azetidinyl)benzonitrile (P4C) in water-tertiary butanol (TBA) mixtures with different alcohol mole fractions is studied using florescence spectroscopy. The P4C absorption spectrum shows a red shift with alcohol concentration in the range of 0.0-0.10 of TBA mole fraction and the spectrum shows a continuous blue shift for the entire range of alcohol concentration on further addition of TBA.

An analysis presents the results of several time-resolved fluorescence emission studies that are used to analyze the dependence of the excited-state intramolecular charge-transfer reaction in (alkylamino)benzonitriles on ion-size and the concentration of the electrolyte.

Electrospray ionization (ESI) was used to generate gas-phase doubly charged complex ions composed of the uranyl ion and nitrile ligands. In general, for species with 0-3 nitrile ligands, two general reaction pathways were observed, through the formation of adducts and through charge reduction reactions.

The stationary points on the potential surfaces for a number of gas phase S(sub N)2 reactions are determined using a combination of pulsed ionization high-pressure mass spectroscopy. The resulting structures support the description of binding as a mixture of hydrogen bonding and ion-dipole bonding.

(S)-(-)-2-chloropropionitrile is prepared from (S)-(+)-alanine, and the ORD curves are obtained in several solvents and in the gas phase. The specific rotations calculated at the B3LYP/aug-cc-pVDZ level including electric field dependent functions are in agreement with the measured gas phase values.