TY - JOUR
T1 - Calculated absolute cross section for the electron-impact ionisation of simple molecular ions
AU - Deutsch, H.
AU - Becker, K.
AU - Defrance, P.
AU - Onthong, U.
AU - Probst, M.
AU - Matt, S.
AU - Scheier, P.
AU - Märk, T. D.
N1 - Funding Information:
This work has been carried out within the Association EURATOM-ÖAW. The content of the publication is the sole responsibility of its publishers and it does not necessarily represent the views of the EU Commission or its services. It was partially supported by the FWF, ÖNB, and ÖAW, Wien, Austria. One of us (K.B.) acknowledges partial financial support from the U.S. National Aeronautics and Space Administration (NASA) under grant NAG5-8971.
PY - 2003/1/15
Y1 - 2003/1/15
N2 - We report the results of the application of the semi-classical Deutsch-Märk (DM) formalism to the calculation of the absolute electron-impact ionisation cross section of the molecular ions H2+, N2+, O2+, CD+, CO+, CO2+, H3O+/D3O+, and CD4+ for which experimental data have been reported. Where available, we also compare our calculated cross sections with calculated cross sections using the BEB method. The level of agreement between the experimentally determined and the calculated cross section is satisfactory only in a few cases. In most cases, the calculated cross sections exceed the measured cross sections, in some cases significantly, which is not surprising in view of the experimental complications in measuring ionisation cross sections of molecular ions due to the presence of competing channels for the formation of fragment ions such as dissociative excitation versus dissociative ionisation.
AB - We report the results of the application of the semi-classical Deutsch-Märk (DM) formalism to the calculation of the absolute electron-impact ionisation cross section of the molecular ions H2+, N2+, O2+, CD+, CO+, CO2+, H3O+/D3O+, and CD4+ for which experimental data have been reported. Where available, we also compare our calculated cross sections with calculated cross sections using the BEB method. The level of agreement between the experimentally determined and the calculated cross section is satisfactory only in a few cases. In most cases, the calculated cross sections exceed the measured cross sections, in some cases significantly, which is not surprising in view of the experimental complications in measuring ionisation cross sections of molecular ions due to the presence of competing channels for the formation of fragment ions such as dissociative excitation versus dissociative ionisation.
KW - Cross section calculations
KW - Electron-impact ionisation
KW - Molecular ions
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U2 - 10.1016/S1387-3806(02)00936-3
DO - 10.1016/S1387-3806(02)00936-3
M3 - Article
AN - SCOPUS:0037437581
SN - 1387-3806
VL - 223-224
SP - 639
EP - 646
JO - International Journal of Mass Spectrometry
JF - International Journal of Mass Spectrometry
ER -