LABORATORY PROJECTS - CHICAGO

Compilation and Analysis of H₃⁺ Spectroscopic Data

       The laboratory spectroscopy of H₃⁺ is also of theoretical interest, as H₃⁺ is a benchmark molecule for variational calculations of ro-vibrational energy levels in polyatomic molecules. In order to facilitate further theoretical calculations on H₃⁺, Mike Lindsay (University of Chicago; now at the University of North Carolina) and I performed a comprehensive re-evaluation of all of the previous spectroscopic work on this fundamental ion. We re-assigned all of the transitions, generated a complete and reliable line list, and used the different types of transitions (fundamental, hot bands, and overtones) to produce a set of experimentally determined energy levels. This set of energy levels contains absolutely no information from theory, which makes it an extremely useful tool for independently evaluating the results of various ab initio calculations.

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