Publication Date

1981

Document Type

Dissertation/Thesis

First Advisor

Russell, Morley

Degree Name

M.S. (Master of Science)

Department

Department of Chemistry

LCSH

Dissociation||Mass spectrometry||Aldehydes

Abstract

An RMU-7 Hitachi Perkin-Elmer spectrometer was modified to allow the study of both the metastable ion (MI) and collision induced dissociation (CID) reactions of acetaldehyde (CH₃CHO) and acetaldehyde -1-d₁ (CH₃CDO). Metastable ion kinetic energy releases (T values) and ion abundance measurements were determined by the high voltage (HV) scanning technique. Mass analyzed Ion Kinetic Energy Spectroscopy (MIKES) was used to determine kinetic energy release values and reactant ion kinetic energy losses (Q values) associated with the collisional excitation of CH₃CHO⁺, CH₃CDO⁺, HCO⁺, and DCO⁺ ions. Ion source fragmentation patterns and collisional activation results are in agreement with predictions based upon the primary isotope effect. The metastable ion decomposition results, however, indicate that some other effect, possibly quantum mechanical tunneling, contributes to the observed T values. This is consistent with a much lower average excess internal energy distribution (ca. 0.1 eV) of the fragmenting molecular ions in metastable ion dissociation relative to that present for ion source or collisionally activated molecular ions (ca. 0.5 eV or more). Other researchers have observed this same effect and have also been unable to satisfactorily explain its source.

Comments

Includes bibliographical references.||Includes illustrations.

Extent

v, 68 pages

Language

eng

Publisher

Northern Illinois University

Rights Statement

In Copyright

Rights Statement 2

NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors.

Media Type

Text

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