The Microwave Spectroscopy of Small Molecules with Methyl Rotors

Author

Ian Finneran

Date of Award

2011

Document Type

Thesis

Degree Name

Bachelors

Department

Natural Sciences

First Advisor

Shipman, Steven

Keywords

Microwave Spectroscopy, Methyl Rotors, Chirped-Pulse, Physical Chemistry

Area of Concentration

Chemistry

Abstract

The microwave spectra of three molecules with methyl rotors, 2-methylfuran, o-fluorotoluene, and anisole, were collected between 8.7-18.3 GHz using a waveguide chirped-pulse Fourier-transform microwave spectrometer at 273 K, 298 K, and 323 K. The splittings due to the methyl torsion were used to calculate the barrier height to internal rotation of the methyl rotor in 2-methylfuran (411 cm-1) and o-fluorotoluene (238 cm-1), and these values were compared to the values predicted by ab initio (B3LYP/6-311+G(d,p) model chemistry) calculations (369 cm-1 and 205 cm-1, respectively). One torsionally excited state was fit in 2-methylfuran, and two were fit in o-fluorotoluene. No splittings were observed in the spectrum of anisole, which indicates that the barrier height is at least 1100 cm-1. The development of a Python brute force automated spectral fitting program and an Arduino-based pressure controller are also discussed.

Rights

This bibliographic record is available under the Creative Commons CC0 public domain dedication. The New College of Florida, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.

This document is currently not available here.

Share

COinS