Project abstract for group leopoldd

Metal Cluster Structures and Reactivities: Computational Elucidation of Anion Photoelectron Spectra

This group investigates the bonding and chemistries of small transition metal clusters in the gas phase, through a combination of experimental and computational techniques. Their experiments employ anion photoelectron spectroscopy and flow tube ion-molecule reactivity studies using mass spectrometry, and their calculations are performed with Gaussian's density functional methods. Computational predictions by themselves or others of the geometries, vibrational frequencies, and ground and excited electronic state energies of neutral and negatively charged clusters help elucidate the spectroscopic data and aid in electronic and vibrational assignments. The calculations can also provide information about properties not directly measurable in the group's experiments, such as the geometries, spin multiplicities, charge distributions, and electron configurations of the observed electronic states. These spectroscopic studies can also provide useful benchmarks to aid in the further development, by other researchers, of improved theoretical methods and basis sets with which to treat these small but computationally challenging systems. Current work by this group includes studies of neutral and anionic bimetallic dimers incorporating group 5 and 6 transition metals, which exhibit high order multiple bonding, and of organometallic anions produced upon reaction of early transition metal atoms and small clusters with simple hydrocarbons, such as ethylene and butadiene. These results can potentially contribute to the understanding of the relationships between the electronic and molecular structures of the ground and low-lying excited electronic states of transition metal clusters and their chemical reactivities, and thus can provide insights that may be useful in the design and synthesis of more highly selective catalytic materials.