We report on a combination of experimental and theoretical investigations into the elastic differential cross sections (DCS) and integral cross sections (ICS) for electron interactions with dichloromethane, CH 2 Cl 2 , in the incident electron energy over the 7.0-30 eV range. Elastic electron scattering cross section calculations have been performed within the framework of the Schwinger multichannel method implemented with pseudopotentials (SMCPP), and the independent atom model with screening corrected additivity rule including interference effects correction (IAM-SCAR+I). The present elastic DCSs have been found to agree reasonably well with the results of IAM-SCAR+I calculations above 20 eV, and also with the SMC calculations below 30 eV. Although some discrepancies were found for 7 eV, the agreement between the two theoretical methodologies is remarkable as the electron impact energy increases. Calculated elastic DCSs are also reported up to 1000 eV for scattering angles from 0º to 180º together with total cross section (TCS) within the IAM-SCAR+I framework.

Articles you may be interested inElectronic excitation of carbonyl sulphide (COS) by high-resolution vacuum ultraviolet photoabsorption and electron-impact spectroscopy in the energy region from 4 to 11 eV J. Chem. Phys. 142, 064303 (2015); 10.1063/1.4907200Valence and ionic lowest-lying electronic states of ethyl formate as studied by high-resolution vacuum ultraviolet photoabsorption, He(I) photoelectron spectroscopy, and ab initio calculations J. Chem. Phys. 141, 104311 (2014) The electronic spectroscopy of isolated furfural (2-furaldehyde) in the gas phase has been investigated using high-resolution photoabsorption spectroscopy in the 3.5-10.8 eV energy-range, with absolute cross section measurements derived. Electron energy loss spectra are also measured over a range of kinematical conditions. Those energy loss spectra are used to derive differential cross sections and in turn generalised oscillator strengths. These experiments are supported by ab initio calculations in order to assign the excited states of the neutral molecule. The good agreement between the theoretical results and the measurements allows us to provide the first quantitative assignment of the electronic state spectroscopy of furfural over an extended energy range. C 2015 AIP Publishing LLC. [http://dx

We present the experimental high-resolution vacuum ultraviolet (VUV) photoabsorption spectra of phenol covering for the first time the full 4.3-10.8 eV energy-range, with absolute cross sections determined. Theoretical calculations on the vertical excitation energies and oscillator strengths were performed using time-dependent density functional theory and the equation-of-motion coupled cluster method restricted to single and double excitations level. These have been used in the assignment of valence and Rydberg transitions of the phenol molecule. The VUV spectrum reveals several new features not previously reported in the literature, with particular reference to the 6.401 eV transition, which is here assigned to the 3sσ/σ(∗)(OH)←3π(3a″) transition. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of phenol in the earth's atmosphere (0-50 km).

We investigate the methanol absorption spectrum in the range 5.5− 10.8 eV to provide accurate and absolute cross-sections values. The main goal of this study is to provide a comprehensive analysis of methanol electronic-state spectroscopy by employing high-resolution vacuum ultraviolet (VUV) photoabsorption measurements together with state-of-the-art quantum chemical calculation methods. The VUV spectrum reveals several new features that are not previously reported in literature, for n > 3 in the transitions (nsσ(a′) ← (2a″)) ( 1 A′ ← X ̃1A′) and (nsσ, npσ, npσ′, ndσ ← (7a′)) ( 1 A′ ← X ̃1A′), and with particular relevance to vibrational progressions of the CH 3 rocking mode, v 11 ′ (a″), mode in the (3pπ(a″) ← (2a″)) (2 1 A′ ← X ̃1A′) absorption band at 8.318 eV. The measured absolute photoabsorption cross-sections have subsequently been used to calculate the photolysis lifetime of methanol in the Earth's atmosphere from the ground level up to the limit of the stratosphere (50 km altitude). This shows that solar photolysis plays a negligible role in the removal of methanol from the lower atmosphere compared with competing sink mechanisms. Torsional potential energy scans, as a function of the internal rotation angle for the ground and first Rydberg states, have also been calculated as part of this investigation.

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