Total cross section measurements for electron scattering from dichloromethane.

Using our magnetically confined electron transmission apparatus, we report the results of total cross sections (TCSs) for electron scattering from dichloromethane (CHCl). The energy range of this study is 1-300 eV. Wherever possible, the present data are compared to earlier measured TCSs of Wan [J. Chem. Phys. , 1865 (1991)] and Karwasz [Phys. Rev. A , 1341 (1999)] and to the corresponding theoretical independent atom model with screening corrected additivity rule and interference term (IAM-SCAR+I) results of Krupa [Phys. Rev. A , 042702 (2018)] and a spherical complex optical potential formulation calculation of Naghma [J. Electron Spectrosc. Relat. Phenom. , 48 (2014)]. Within their respective uncertainties, the present TCS and those of Karwasz are found to be in very good agreement over their common energy range. However, agreement with the results of Wan is quite poor. The importance of the experimentally inherent 'missing angle' effect (see later) on the measured TCS is investigated and found to be significant at the lower energies studied. Indeed, when this effect is accounted for, agreement between our measured TCSs and the corrected IAM-SCAR+I+rotations calculation results are, for energies above about 3 eV, in good accord (to better than 8%). Finally, we observe two shape resonances, consistent with the earlier electron transmission spectroscopy results of Burrow [J. Chem. Phys. , 2699 (1982)], at about 2.8 eV and 4.4 eV incident electron energy, in our measured TCS.