Combining High Performance Mass Spectrometry and Cryogenic Ion Spectroscopy for Structure Determinations of Exotic Molecules and Reaction Intermediates
Date of Award
Doctor of Philosophy (PhD)
High-performance mass spectrometry is a staple for analytical chemistry in a vast number of industries and academic settings. In recent years, gas-phase analysis of highly reactive species has become prevalent, as isolation of these intermediates provides fundamental chemical insight. Collision-induced dissociation (CID) is a technique that is leveraged to generate these reactive species. Paired with mass spectrometry, cryogenic ion spectroscopy provides sharp vibrational spectra that allows for accurate structural comparison to electronic structure calculations. The combination of these two techniques enables the structure determination of a new class of ions and complexes. In this dissertation, the details of the integration of a commercial high-resolution mass spectrometer to the cryogenic vibrational predissociation spectroscopy experiment are reported. Proof of principle experiments were conducted using a dipeptide (phenylalanyltyrosine) with a canonical CID fragmentation pattern. Following this experiment, a ruthenium-based substrate was isolated with a double hydrogen acceptor for elucidation of the hydrogen bonding interactions involved in a proton-coupled electron transfer reaction. Continuing the investigation of metal-mediated chemistry, a nickel complex ion was reduced into the active oxidation state in solution, and then exposed to various small molecules for chemical analysis. Finally, formation of highly reactive carbanions was achieved by decarboxylation via CID. Structural analysis revealed intramolecular C-C bond formation and isomeric studies elucidated the structural effect of circumambulatory charge migration.
Perez, Evan Hunt, "Combining High Performance Mass Spectrometry and Cryogenic Ion Spectroscopy for Structure Determinations of Exotic Molecules and Reaction Intermediates" (2022). Yale Graduate School of Arts and Sciences Dissertations. 510.