Lia Yeh


Robust Autonomous Assignment of Rigid Rotors

The assignment problem in microwave spectroscopy is the task of identifying a molecule’s set of three rotational constants, inversely proportional to the moments of inertia about its principle axes. These microwave spectra and their corresponding rotational constants are a unique "fingerprint" of the rigid rotor molecule. Given that it has been assigned before, we can use this spectra to determine whether the molecule is present in an unknown mixture. Although a handful of experts in the field can discern periodicity in simple spectra, the assignment problem is difficult, time-consuming, and contains multitudes of edge cases. Existing software uses the bottom-up approach of requiring an initial guess to offset costly enumeration of all possibilities in an otherwise impractically large search space. By automating the top-down, pattern-finding approach, our software eliminates guesswork, accelerates the necessary computation, analyzes data more robustly in higher dimensions, and visually presents these findings to a broader scientific audience. Alongside our ongoing work identifying commonalities in spectra and calculating substitutional atom coordinates, our long-term objective is to draw an unknown, previously unassigned molecule's carbon, nitrogen, and oxygen structure given its microwave spectra.

UC Santa Barbara Center for Science and Engineering Partnerships UCSB California NanoSystems Institute UC Santa Barbara’s Parents Fund Campaign for UC Santa Barbara