Comment on “Dynamical (e, 2e) studies using tetrahydrofuran as a DNA analog” [J. Chem. Phys. 133, 124302 (2010)]

Cross section data for electron scattering from DNA are important for modelling radiation damage in biological systems. Triply differential cross sections for the electron impact ionization of the highest occupied outer valence orbital of tetrahydrofurfuryl alcohol, which can be considered as an analogue to the deoxyribose backbone molecule in DNA, have been measured using the (e,2e) technique. The measurements have been performed with coplanar asymmetric kinematics at an incident electron energy of 250 eV, an ejected electron energy of 20 eV, and at scattered electron angles of −5 • , −10 • , and −15 • . Experimental results are compared with corresponding theoretical calculations performed using the molecular 3-body distorted wave model. Some important differences are observed between the experiment and calculations.

Section: Resultsmentioning

confidence: 88%

Dynamical (e,2e) studies of tetrahydrofurfuryl alcohol

Bellm

Builth-Williams

Jones

et al. 2012

“…Previously Xu et al 44 have suggested that the origins of the observed binary-to-recoil ratio may be related to the electron momentum profile of the ionized molecular orbital. In earlier studies on THF, 12-15 the behavior of the binary to recoil ratios with respect to the variations in kinematical conditions could be qualitatively explained by relating the kinematical conditions to the ionized orbitals electron momentum profile.…”

Section: Resultsmentioning

confidence: 96%

A dynamical (e,2e) investigation of the structurally related cyclic ethers tetrahydrofuran, tetrahydropyran, and 1,4-dioxane

Builth-Williams¹,

Bellm²,

Chiari³

et al. 2013

Triple differential cross section measurements for the electron-impact ionization of the highest occupied molecular orbitals of tetrahydropyran and 1,4-dioxane are presented. For each molecule, experimental measurements were performed using the (e,2e) technique in asymmetric coplanar kinematics with an incident electron energy of 250 eV and an ejected electron energy of 20 eV. With the scattered electrons being detected at −5°, the angular distributions of the ejected electrons in the binary and recoil regions were observed. These measurements are compared with calculations performed within the molecular 3-body distorted wave model. Here, reasonable agreement was observed between the theoretical model and the experimental measurements. These measurements are compared with results from a recent study on tetrahydrofuran [D. B. Jones, J. D. Builth-Williams, S. M. Bellm, L. Chiari, C. G. Ning, H. Chaluvadi, B. Lohmann, O. Ingolfsson, D. Madison, and M. J. Brunger, Chem. Phys. Lett. 572, 32 (2013)] in order to evaluate the influence of structure on the dynamics of the ionization process across this series of cyclic ethers.

“…In our earlier investigations on other molecular targets, conducted under similar kinematical conditions, prominent recoil peak intensities have been observed (especially for θ a = −5 • ). Previously, Xu et al 38 have commented that the strength of the recoil peak intensity could be related to the orbital momentum profile. In that work, they stated that the p-like profile, having a reduced binary maximum, may ex-hibit a larger recoil peak, relatively speaking.…”

Section: Resultsmentioning

confidence: 99%

Triply differential (e,2e) studies of phenol

Silva

Neves

Chiari

et al. 2014

We have measured (e,2e) triple differential cross sections (TDCS) for the electron-impact ionisation of phenol with coplanar asymmetrical kinematics for an incident electron energy of 250 eV. Experimental measurements of the angular distribution of the slow outgoing electrons at 20 eV are obtained when the incident electron scatters through angles of -5°, -10°, and -15°, respectively. The TDCS data are compared with calculations performed within the molecular 3-body distorted wave model. In this case, a mixed level of agreement, that was dependent on the kinematical condition being probed, was observed between the theoretical and experimental results in the binary peak region. The experimental intensity of the recoil features under all kinematical conditions was relatively small, but was still largely underestimated by the theoretical calculations.