Parameter-free model of the correlation-polarization potential for electron-molecule collisions

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: B Triple Differential Cross Sectionsmentioning

confidence: 99%

Dynamical (e,2e) studies of tetrahydrofurfuryl alcohol

Bellm

Builth-Williams

Jones

et al. 2012

“…Note that the corresponding details of our calculations on THF can be found elsewhere. 15 U E is the exchange potential of Furness-McCarthy (corrected for sign errors), 26 which approximates the effect of the continuum electron exchanging with the passive bound electrons in the molecule, and U CP is the correlation-polarization potential of Perdew and Zunger 27 (see also Padial and Norcross 28 ).…”

Section: Theoretical Detailsmentioning

confidence: 99%

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.

“…U E is the exchange potential of Furness and McCarthy (corrected for sign errors) 31 which approximates the effect of the continuum electron exchanging with the passive bound electrons in the molecule, and U CP is the correlation-polarization potential of Perdew and Zunger. 32,33 The final state for the system is approximated as a product of distorted waves for the two continuum electrons times the average Coulomb-distortion factor. The final state distorted waves are calculated as the initial state except that the final state spherically symmetric static distorting potential for the molecular ion is used for U s .…”

Section: Theoretical Frameworkmentioning

confidence: 99%

Experimental and theoretical investigation of the triple differential cross section for electron impact ionization of pyrimidine molecules

Builth-Williams

Bellm

Jones

et al. 2012

Cross-section data for electron impact induced ionization of bio-molecules are important for modelling the deposition of energy within a biological medium and for gaining knowledge of electron driven processes at the molecular level. Triply differential cross sections have been measured for the electron impact ionization of the outer valence 7b2 and 10a1 orbitals of pyrimidine, using the (e, 2e) technique. The measurements have been performed with coplanar asymmetric kinematics, at an incident electron energy of 250 eV and ejected electron energy of 20 eV, for scattered electron angles of −5°, −10°, and −15°. The ejected electron angular range encompasses both the binary and recoil peaks in the triple differential cross section. Corresponding theoretical calculations have been performed using the molecular 3-body distorted wave model and are in reasonably good agreement with the present experiment.