Cross sections for elastic electron collisions on two hydrocarbon compounds:n-butane and benzene in the intermediate-energy range

Abstract

In this work, we report an experimental-cross-section determination of elastic electron collisions with two hydrocarbon species, namely n-butane and benzene, in the intermediate-energy range. More specifically, absolute differential, integral and momentum-transfer cross sections are measured and reported in the (50–1000) eV range. The measurements were performed using a crossed electron beam–molecular beam geometry. The angular distributions of the scattered electrons were converted to absolute cross sections using the relative flow technique. Integral and momentum-transfer cross sections are derived from the measured differential cross sections. Additionally, elastic cross sections are also calculated using the independent atom model at the static-exchange-polarization level of approximation. A comparison of our measured data with calculated and other experimental results available in the literature is made.

Absorption effects in electron–sulfur-dioxide collisions

“…Nevertheless, it is quite surprising to notice that their results become more discrepant with both our experimental and calculated data with increasing incident energies. Since the IAM is based on a Born-type perturbative approximation, it is expected that it should be more accurate at higher incident energies as already shown in several previous studies [62,63]. Thus, we can not provide a physical reason for the energy-dependent behavior of their calculated results.…”

Differential elastic electron scattering by pentane

“…Propane: Boesten et al [10] and Souza et al [12]. Butane: Sanches et al [13]. Pentane: • Present experiment and present calculations.…”

“…9 where we compare our experimental DCS for pentane (C 5 H 12 ) with available DCS experimental data for shorter linear alkanes C n H 2n+2 from this family such as ethane (C 2 H 6 ), propane (C 3 H 8 ), and butane (C 4 H 10 ). While there are low and intermediate E 0 (<50 eV) elastic DCSs for ethane and propane, only intermediate E 0 (> 50 eV) DCSs exist for butane [13].…”

“…Ignition and reaction chemistry involving excitation, dissociation, and ionization of these molecules in combustion (plasma) processes in automobile engines [3] is governed or catalyzed by energetic electron scattering from these fuel species in the energy region which ranges from 0.1 eV to high energies (>100 eV), but with a maximum around 10 eV [4]. Whereas there exist electron impact data on methane [5][6][7], ethane [8,9], propane [10][11][12], and butane [13], and in references cited within these, there is lack of electron collision data for pentane. The few data available for pentane are those by Freeman et al [14] of total electron cross sections determined from the mobility of electrons in liquid pentane at the energies of 0.1 to 0.5 eV using a time-of-flight method and those by Kimura et al [15] of gaseous pentane of total cross sections for this target.…”

A study of electron scattering from benzene: Excitation of the 1B1u, 3E2g, and 1E1u electronic states

“…Experimental grand total cross sections, covering a fairly wide energy range, have been reported by several groups, [7][8][9][10][11] while dissociative excitation cross sections (30-1000 eV) were measured using a radiation emission technique by Beenakker and de Heer. 12 Elastic scattering cross section measurements have been made by Gulley and Buckman, 13 Cho et al 14 Boechat-Roberty et al, 15 and most recently from Sanches et al 16 Relatively speaking, quite a few experimental investigations into vibrational excitation and resonance effects, at energies below 10 eV, have been published. These include the studies by Schulz and coworkers [17][18][19][20] and Mathur and Hasted.…”