Tholins: A Gas Phase Computational Study of Methanimine and Related Species

<p>Titan has been referred to as the “gem of the Solar System.” This significance comes from its dense atmosphere, which is the only atmosphere in our Solar System other than Earth’s that is dense enough to produce a hydrological cycle (or methanological cycle, in the case of Titan). Scientists in the fields of astrobiology and astrochemistry believe that Titan’s current atmospheric conditions could resemble that of the primordial Earth, and as such is being studied to further our understanding of how life forms. While Titan’s atmosphere contains an abundance of organic molecules, methanimine (MA) and it’s related species the methyl amino radical (MAR) and methyleneamine cation (MEC) are of particular interest. Scientists believe that MA, MAR, and MEC are precursors to organic aerosols called Tholins, which are defined as nitrogen-containing molecules that are thought to be precursors to amnio acids. The purpose of this research is to answer crucial questions to understand the role of these molecules in Titan’s atmospheric chemistry. To do this, a gas phase chemical model is employed. The expected outcomes of the computational work are threefold: 1) determine the major formation and destruction reactions for MA and related species, 2) obtain the most up-to-date rate coefficients for those reactions, and 3) obtain abundance versus time data for MA and related species. Tholin production is observed at most altitudes, but this research focuses on the upper atmosphere (500+ km), which has largely been unstudied until recent years. While MA, MAR, and MEC have all been studied, a comprehensive list of reactions and rate coefficients has not been completed since 2010. The data from this study suggest that MA, MAR, and MEC are present at concentrations deemed important for tholin production, and agrees with data presented by other chemical models. </p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Master's

Discipline thesis:degree_discipline

Chemistry

Grantor dc:publisher

Eastern Kentucky University

Year

2022

Author dc:creator

• Chem, Bradley T

• methanimine
• tholins
• Titan
• Atmospheric Sciences

Statement dc:rights

• Copyright 2022 Bradley T Chem

Repository record dc:identifier

https://encompass.eku.edu/etd/696

OAI identifier oai:identifier

oai:encompass.eku.edu:etd-1694