Title

Doubly charged ion mass spectra of alkyl-substituted furans and pyrroles

ACS Citation

Nelson, P. R.; Fung, C.; SedgwickK, J. B.; Shields, G. C.; Abbey, L. E.; Moran, T. F. Doubly Charged Ion Mass Spectra of Alkyl-Substituted Furans and Pyrroles. Org. Mass Spectrom. 1987, 22 (7), 389-€“399.

Abstract

Doubly charged ion mass spectra of alkyl-substituted furans and pyrroles were obtained using a double-focusing magnetic mass spectrometer operated at 3.2 kV accelerating voltage. Molecular ions were the dominant species found in doubly charged spectra of lower molecular weight heterocydic compounds, whereas the spectra of the higher weight homologues were typified by abundant fragment ions from extensive decomposition. Measured doubly charged ionization and appearance energies ranged from 22.8 to 47.9 eV. Ionization energies were correlated with values calculated using self-consistent field–molecular orbital techniques. A multichannel diabatic curve-crossing model was developed to investigate the fundamental organic ion reactions responsible for development of doubly charged ion mass spectra. Probabilities for Landau–Zener type transitions between reactant and product curves were determined and used in the collision model to predict charge-transfer cross-sections, which compared favorably with experimental cross-sections obtained using time-of-flight techniques.

Source Name

Organic Mass Spectrometry

Publication Date

1987

Volume

22

Issue

7

Page(s)

389-399

Document Type

Citation

Citation Type

Article