Kevin Roenitz

Graduate Student

Emory University

Office: 131 Atwood Hall

1515 Dickey Drive

Atlanta, GA 30322-2210

phone: 404-727-6573

fax: 404-727-6586

Educational Background

B.A. in Chemistry from Illinois Wesleyan University (2015)
Graduate student in Chemistry from Emory University

Current Research

My current research focuses on small organic ions that have astrochemical interest. In the interstellar medium (ISM), ionization typically begins with cosmic-ray radiation striking a H2 molecule to produce H2+ and thus start the process from which H3+ is formed. H3+ is a major proton donor in the ISM and is thought to readily protonate small organic molecules such as formaldehyde and methanol. Both of these organics should readily accept a proton and have rotational transitions. Protonated formaldehyde and protonated methanol are thought to important ions in interstellar chemistry, specifically prebiotic chemistry. It is thought that these can help us determine where amino acids form. Whether it be in the ISM and then transfered to planets via comets and astroids or the building blocks of amino acids are simply transfer to planets and formed after impact. This can help us begin to understand how life began in our galaxy. In addition to the prebiotic chemistry, we are interested in complex ions like H5+. This ion is theorized to be made in the ISM when H3+ reacts with neutral H2. Numberous studies predict H5+ to be only have rotational transitions for certain isotopologues that have dipole moments.

The experimental techniques that I employ are a supersonic expansion discharge source for the production of rotationally cooled ions, and liquid nitrogen cooled hollow cathode for the production of protonated species in a flow cell. After these protonated ions are produced, we record their rotational spectra. Once we have a rotational spectra, we can then compare our spectra to those collected by radio astronomy and determine if the ions we produce can be seen in the ISM. A multipass optical alignment is used to increase sensitivity for the supersonic expansion discharge source. To decrease the time it takes to record the rotational transitions of our molecules, a fast-sweep method developed by the lab is used. Currently work is being done to upgrade the sensitivity of our instrumentation by converting the multipass optical alignment to an optical cavity. Additionally, work has be conducted in order to improve spectral assignment by using microwave-millimeter/submillimeter double resonance spectroscopy.

The current molecules I am working on are protonated formaldehyde with the goal to produce and record the THz spectrum of protonated methanol. Additionally, the isotopologues of H3+ and possibly H5+ are another major area of focus for my research. Lastly, I am working on developing new instrumentation to be used in this lab and possibly elsewhere.

Refereed Publications

  • Roenitz, K. M.; Hays, B. M.; Powers, C.; McCabe, M. N.; Smith, H.; Widicus Weaver, S. L. AC Stark Effect Observed in a Microwave-Millimeter/Submillimeter Wave Double Resonance Experiment. (In Preparation).

Conference Talks

  • Kevin Roenitz, Luyao Zou, & Susanna L. Widicus Weaver, "Extending the Millimeter-Submillimeter Spectrum of Protonated Formaldehyde", International Symposium on Molecular Spectroscopy, 2017, Champaign-Urbana, IL