Title

Fragmentation of Energy Selected CFC-1X ions

Poster Number

30

Lead Author Affiliation

Chemistry

Additional Authors

J. Csontos and M. Kallay

Introduction

Diethyl ether (DEE) is a common, organic molecule widely used as a solvent, engine starting fluid, and as an octane and oxygen enhancer in internal combustion engines. DEE has also been known to become unstable and spontaneously form peroxides in air, which makes the oxidation mechanism of DEE of interest. Thermochemical input parameters have been shown to be a major source of uncertainty in combustion models, spurring us to revisit the dissociative photoionization to confirm or revise the enthalpies of formation.

Purpose

To confirm or revise the previously published and currently used ionization energy of DEE and enthalpies of formation of DEE and its daughter ions.

Method

In this study, DEE is analyzed using imaging photoelectron photoion coincidence spectroscopy (iPEPICO) at the Swiss Light Source (SLS) in Villigen, Switzerland. Quantum chemical calculations using the B3LYP/6-311++G(d,p) level of theory and G4, CBS-APNO, DFT, and STQN methods were used to determine internal energy distributions and transition states of the fragment ions. The heats of formations and fragmentation pathways were determined through RRKM modeling methods.

Results

Through thermochemical calculations, we conclude that the previous published IE of DEE by Botter et al, rather than the NIST IE value, is correct and that the vertical and adiabatic IE coincide. Enthalpies of formation and appearance energies of DEE fragments were also determined and compared to existing values.

Significance

Values have been determined for enthalpies of formation and appearance energies of DEE and its fragments and are used to either confirm or revise existing values.

Location

DeRosa University Center, Stockton campus, University of the Pacific

Format

Poster Presentation

This document is currently not available here.

Share

COinS
 
Apr 25th, 2:00 PM Apr 25th, 4:00 PM

Fragmentation of Energy Selected CFC-1X ions

DeRosa University Center, Stockton campus, University of the Pacific

Diethyl ether (DEE) is a common, organic molecule widely used as a solvent, engine starting fluid, and as an octane and oxygen enhancer in internal combustion engines. DEE has also been known to become unstable and spontaneously form peroxides in air, which makes the oxidation mechanism of DEE of interest. Thermochemical input parameters have been shown to be a major source of uncertainty in combustion models, spurring us to revisit the dissociative photoionization to confirm or revise the enthalpies of formation.