Date of Award

1997

Document Type

Restricted Thesis

Terms of Use

© 1997 Brian Schwartz. All rights reserved. Access to this work is restricted to users within the Swarthmore College network and may only be used for non-commercial, educational, and research purposes. Sharing with users outside of the Swarthmore College network is expressly prohibited. For all other uses, including reproduction and distribution, please contact the copyright holder.

Degree Name

Bachelor of Arts

Department

Physics & Astronomy Department

First Advisor

Thomas D. Donnelly

Abstract

Nitrous oxide, N₂O, is a greenhouse gas which plays a role in atmospheric ozone destruction. Known terrestrial N₂O sources do not account for its abundance (300 ppbv) in the atmosphere. We performed matrix isolation experiments to determine if N₂, reacting with electronically excited O₂(O₂*(H)), is an atmospheric N₂O source. A matrix is a thin crystal formed by depositing a gas onto a substrate sufficiently cold to solidify the molecules. We first looked at N₂O doped in matrices of N₂, O₂, and a mixed N₂/O₂ matrix. This data was used to identify photogenerated N₂O in an N₂/O₂ matrix and determine its matrix environment. N₂O was formed by irradiating undoped mixed N₂/O₂ matrices with UV light capable of exciting O₂ to O₂*(H). O₂*(H) reacts with O₂ to make O₃, which can be dissociated into O₂ and O(¹D). Since N2 + O(¹D) → N₂O, the mere presence of N₂O in the irradiated sample does not prove O₂*(H) as an N₂O source. As our apparatus allowed for in situ matrix isolation spectroscopy, N₂O and O₃ growth curves were generated and evaluated to determine whether N₂ + O₂*(H) → N₂O + O occurred. Since our data was inclusive, we propose another matrix isolation experiment to determine whether O₂*(H) is an N₂O source.

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