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The tunable diode laser spectroscopy method is useful to calculate geometrical isomerization of labeled cyclopropane rate constants and offers several improvements over infrared spectroscopic method. These include enhanced resolution over a small fractional wave number range, permitting the distinctions between vibrational-rotational transitions due to stereochemically divergent labeled isomers.

Equation of motion coupled cluster calculations were performed on various structures of OH in clusters with one, two, three, and four water molecules to determine the energies of valence and charge transfer states. Motivation for these calculations is to understand the absorption spectrum of OH in water. Previous calculations on these species have confirmed that the longer wavelength transition observed is due to the A(²Σ) X(²Π) valence transition, while the shorter wavelength transition is due to a charge-transfer from H2O to OH. While these previous calculations identified the lowest energy charge-transfer state, our calculations have included sufficient states to identify additional solvent-to-solute charge transfer states. The minimum energy structures of the clusters were determined by application of the Monte Carlo technique to identify candidate cluster structures, followed by optimization at the level of second-order M0ller-Plesset perturbation theory. Calculations were performed on two structures of OH-H2O, three structures of OH-(H2O)2, four structures of OH-(H2O)3, and seven structures of OH-(H2O)4. Confirming previous calculations, as the number of water molecules increases, the energies of the excited valence and charge-transfer states decrease; however, the total number of charge-transfer states increases with the number of water molecules, suggesting that in the limit of OH in liquid water, the charge-transfer states form a band. [ABSTRACT FROM AUTHOR]

Investigates the coupled-cluster calculations of mono and difluorides of krypton. Results of krypton difluoride triplet calculations; Presentation of the minimum energy geometry of the krypton-fluorine van der Waals complex; Identification of the krypton monofluoride cation and the ground singlet state of krypton difluoride.

Reports on aqueous cluster studies that have led to a reassessment of electronic properties of bulk water, such as band gap, conduction band edge and vacuum level. Presentation of results in an energy diagram for bulk water which shows the utility of exploring the conduction band of water as a function of solvent polarization.