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TDCS Calculation for the Ionization of Nitrogen Molecule by Electron Impact. ATOMS 2022. [DOI: 10.3390/atoms10020050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Triple differential cross section (TDCS) results are reported for the electron impact ionization of nitrogen molecules. The TDCSs have been calculated in distorted wave Born formalism using orientation averaged molecular orbital (OAMO) approximation. The TDCS results are presented as average and weighted sum for the outer molecular orbital 3σg, 1πu, 2σu and the inner 2σg molecular orbital. The obtained theoretical TDCSs are compared with the available measurements. The results are analysed in terms of the positions and relative intensities of binary and recoil peaks. Within a first order model and for a complex molecule, a reasonable agreement is obtained with the experimental data in the binary peak region with certain discrepancies in position and magnitude in the recoil peak region.
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2
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Jones D, Ali E, Chakraborty H, Ning C, García G, Madison D, Brunger M. A dynamical (e,2e) investigation into the ionization of pyrazine. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2021.139000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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3
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Calculation of Electron Impact Single Ionization TDCS of Tungsten Atoms at 200, 500 and 1000 eV. ATOMS 2021. [DOI: 10.3390/atoms9020031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
We report triple differential cross-sections (TDCSs) for the electron impact single ionization of tungsten atoms for the ionization taking place from the outer sub shells of tungsten atoms, viz. W (6s), W (5d), W (5p) and W (4f). The study of the electron-induced processes such as ionization, excitation, autoionization from tungsten and its charged states is strongly required to diagnose and model the fusion plasma in magnetic devices such as Tokamaks. Particularly, the cross-section data are important to understand the electron spectroscopy involved in the fusion plasma. In the present study, we report TDCS results for the ionization of W atoms at 200, 500 and 1000 eV projectile energy at different values of scattered electron angles. It was observed that the trends of TDCSs for W (5d) are significantly different from the trends of TDCSs for W (6s), W (5p) and W (4f). It was further observed that the TDCS for W atoms has sensitive dependence on value of momentum transfer and projectile energy.
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Abstract
A review on the positron scattering from atoms and molecules is presented in this article. The focus on positron scattering studies is on the rise due to their presence in various fields and application of cross section data in such environments. Positron scattering is usually investigated using theoretical approaches that are similar to those for electron scattering, being its anti-particle. However, most experimental or theoretical studies are limited to the investigation of electron and positron scattering from inert gases, single electron systems and simple or symmetric molecules. Optical potential and polarized orbital approaches are the widely used methods for investigating positron scattering from atoms. Close coupling approach has also been used for scattering from atoms, but for lighter targets with low energy projectiles. The theoretical approaches have been quite successful in predicting cross sections and agree reasonably well with experimental measurements. The comparison is generally good for electrons for both elastic and inelastic scatterings cross sections, while spin polarization has been critical due to its sensitive perturbing interaction. Positron scattering cross sections show relatively less features than that of electron scattering. The features of positron impact elastic scattering have been consistent with experiment, while total cross section requires significant improvement. For scattering from molecules, utilization of both spherical complex optical potential and R-matrix methods have proved to be efficient in predicting cross sections in their respective energy ranges. The results obtained shows reasonable comparison with most of the existing data, wherever available. In the present article we illustrate these findings with a list of comprehensive references to data sources, albeit not exhaustive.
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5
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Ali E, Chakraborty HS, Madison DH. Improved theoretical calculations for electron-impact ionization of DNA analogue molecules. J Chem Phys 2020; 152:124303. [PMID: 32241131 DOI: 10.1063/1.5143148] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ionizing interactions between charged particles and molecules of biological relevance have attracted considerable interest in the last decade due to its importance in medical radiation therapy. We have previously calculated triply differential cross sections for five biomolecules in collaboration with experimental groups. We used the molecular 3-body distorted wave approximation for these calculations. For ionization of biomolecules, experimentalists are unable to determine the orientation of the molecule at the time of ionization, which means that the calculated cross sections need to be averaged over all molecular orientations. At the time the calculations were performed, it was not numerically feasible for us to perform proper averaging over orientations, so we introduced the orientation averaged molecular orbital approximation to make the calculations possible. We now have the computational capability to properly perform this average, so, here, we present new results with a proper average over orientations and compare with the previous calculations and experiment. Since the original calculations, results from two different distorted-wave models have also been published and the new results will also be compared with those calculations. Overall, the new results are in better agreement with the experiment.
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Affiliation(s)
- Esam Ali
- Department of Natural Sciences, D. L. Hubbard Center for Innovation, Northwest Missouri State University, Maryville, Missouri 64468, USA
| | - H S Chakraborty
- Department of Natural Sciences, D. L. Hubbard Center for Innovation, Northwest Missouri State University, Maryville, Missouri 64468, USA
| | - D H Madison
- Missouri University of Science and Technology, Rolla, Missouri 65402, USA
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Harvey M, Sakaamini A, Patel M, Amami S, Madison D, Murray AJ. Triple differential cross-section measurements for electron-impact ionization of methane from a coplanar geometry to the perpendicular plane. J Chem Phys 2019; 151:194305. [PMID: 31757134 DOI: 10.1063/1.5127121] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A new study of electron-impact single ionization of the HOMO 1t2 state of CH4 has been conducted at incident electron energies 20 eV and 40 eV above the ionization energy of the state. Triple differential cross sections were measured from a coplanar symmetric geometry, where scattered and ionized electrons were detected at equal angles, through to the perpendicular geometry where the outgoing electrons emerged orthogonal to the incident electron beam. At the lower energy, the electrons were detected with equal energies of 10 eV, whereas at the higher energy, data were obtained for equal energies of 20 eV and for unequal energies of 5 eV and 35 eV. The results are compared to a molecular 3-body distorted wave approximation that used a full averaging procedure to allow for the random orientation of the target, an orientation averaged molecular orbital model that averages the target wavefunction over all orientations prior to the collision, and a distorted wave Born approximation that does not include postcollisional interactions.
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Affiliation(s)
- Matthew Harvey
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Ahmad Sakaamini
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Manish Patel
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Sadek Amami
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Don Madison
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Andrew James Murray
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
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Jones DB, Ali E, Ning CG, Ferreira da Silva F, Ingólfsson O, Lopes MCA, Chakraborty HS, Madison DH, Brunger MJ. A dynamical (e,2e) investigation into the ionization of the outermost orbitals of R-carvone. J Chem Phys 2019; 151:124306. [PMID: 31575183 DOI: 10.1063/1.5123526] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
We report an experimental and theoretical investigation into the dynamics of electron-impact ionization of R-carvone. Experimental triple differential cross sections are obtained in asymmetric coplanar kinematic conditions for the ionization of the unresolved combination of the three outermost molecular orbitals (41a-39a) of R-carvone. These cross sections are compared with theoretical cross sections calculated within a molecular 3-body distorted wave (M3DW) framework employing either a proper orientation average or orbital average to account for the random orientation of the molecule probed in the experiment. Here, we observe that the overall scattering behavior observed in the experiment is fairly well reproduced within the M3DW framework when implementing the proper average over orientations. The character of the ionized orbitals also provides some qualitative explanation for the observed scattering behavior. This represents substantial progress when trying to describe the scattering dynamics observed for larger molecules under intermediate-impact energy and asymmetric energy sharing scattering conditions.
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Affiliation(s)
- D B Jones
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia
| | - E Ali
- Department of Natural Sciences, D. L. Hubbard Center for Innovation, Northwest Missouri State University, Maryville, Missouri 64468, USA
| | - C G Ning
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - F Ferreira da Silva
- Atomic and Molecular Collisions Laboratory, CEFITEC, Department of Physics, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - O Ingólfsson
- Department of Chemistry and Science Institute, University of Iceland, 107 Reykjavík, Iceland
| | - M C A Lopes
- Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-900, Brazil
| | - H S Chakraborty
- Department of Natural Sciences, D. L. Hubbard Center for Innovation, Northwest Missouri State University, Maryville, Missouri 64468, USA
| | - D H Madison
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - M J Brunger
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia
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Ali E, Granados C, Sakaamini A, Harvey M, Ancarani LU, Murray AJ, Dogan M, Ning C, Colgan J, Madison D. Triple differential cross sections for electron-impact ionization of methane at intermediate energy. J Chem Phys 2019; 150:194302. [PMID: 31117797 DOI: 10.1063/1.5097670] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report an experimental and theoretical investigation of electron-impact single ionization of the highest occupied molecular orbital 1t2 and the next highest occupied molecular orbital 2a1 states of CH4 at an incident electron energy of 250 eV. Triple differential cross sections measured in two different laboratories were compared with results calculated within the molecular 3-body distorted wave and generalized Sturmian function theoretical models. For ionization of the 1t2 state, the binary peak was observed to have a single maximum near the momentum transfer direction that evolved into a double peak for increasing projectile scattering angles, as has been seen for ionization of atomic p-states. A detailed investigation of this evolution was performed. As expected because of its s-type character, for ionization of the 2a1 state, only a single binary peak was observed. Overall, good agreement was found between experiment and theory.
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Affiliation(s)
- Esam Ali
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - Carlos Granados
- Institut für Physik, Martin-Luther Universität Halle-Wittenberg, 06199 Halle(Saale), Germany
| | - Ahmad Sakaamini
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Matthew Harvey
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | | | - Andrew James Murray
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Mevlut Dogan
- Ecol Academy, Afyon Kocatepe Konutları, CK1, C3-030916 Afyon, Turkey
| | - Chuangang Ning
- Department of Physics, State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing, China
| | - James Colgan
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Don Madison
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
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9
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BEAMDB and MOLD—Databases at the Serbian Virtual Observatory for Collisional and Radiative Processes. ATOMS 2019. [DOI: 10.3390/atoms7010011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
In this contribution we present a progress report on two atomic and molecular databases, BEAMDB and MolD, which are web services at the Serbian virtual observatory (SerVO) and nodes within the Virtual Atomic and Molecular Data Center (VAMDC). The Belgrade Electron/Atom (Molecule) DataBase (BEAMDB) provides collisional data for electron interactions with atoms and molecules. The Photodissociation (MolD) database contains photo-dissociation cross sections for individual rovibrational states of diatomic molecular ions and rate coefficients for the chemi-ionisation/recombination processes. We also present a progress report on the major upgrade of these databases and plans for the future. As an example of how the data from the BEAMDB may be used, a review of electron scattering from methane is described.
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Xu X, Gong M, Li X, Zhang SB, Chen X. Theoretical study of (e, 2e) triple differential cross sections of tetrahydrofuran using multicenter distorted-wave method. J Chem Phys 2018; 148:244104. [PMID: 29960345 DOI: 10.1063/1.5029428] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present in this work a theoretical study of the triple differential cross sections for electron-impact single ionization of 12a' and 9b orbitals of a tetrahydrofuran molecule. The calculations are performed by the multicenter distorted-wave (MCDW) method in coplanar asymmetric kinematics with an incident electron energy of 250 eV, where previous (e, 2e) experiments and theories are available for comparison. The present calculations reproduce the experimental measurements satisfactorily, indicating that the MCDW method can be easily extended to study biomolecules with sufficiently high calculation efficiency.
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Affiliation(s)
- Xiaojie Xu
- Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Maomao Gong
- Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xingyu Li
- Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Song Bin Zhang
- School of Physics and Information Technology, Shaanxi Normal University, Xian 710119, China
| | - Xiangjun Chen
- Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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11
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Purohit G, Kato D. Dependence of electron impact differential cross sections on the ionic charge to radius ratio for the Al 3+(2p) and Be 2+(1s) ions. J Chem Phys 2018; 148:084307. [PMID: 29495759 DOI: 10.1063/1.5016291] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The triple differential cross sections (TDCSs) have been obtained for the electron impact ionization of ionic targets, Al3+(2p) and Be2+(1s), having nearly the same ratio of ionic charge to radius. In the first of this kind of study, the trends of cross sections have been found to match to a greater extent despite ionization taking place from the ionic targets having considerable difference in nuclear charges as well as the ionization taking place from different types of orbitals, p-orbital and s-orbital. The trends of TDCSs have not been found to agree considerably for the neutral Al (3p) and Be (2s) targets.
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Affiliation(s)
- G Purohit
- National Institute for Fusion Science, National Institutes of Natural Sciences, 322-6 Oroshi-Cho, Toki, Gifu 509-5292, Japan
| | - D Kato
- National Institute for Fusion Science, National Institutes of Natural Sciences, 322-6 Oroshi-Cho, Toki, Gifu 509-5292, Japan
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12
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Jones DB, Ali E, Ning CG, Colgan J, Ingólfsson O, Madison DH, Brunger MJ. Electron impact ionization dynamics of para-benzoquinone. J Chem Phys 2016; 145:164306. [DOI: 10.1063/1.4965919] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- D. B. Jones
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide SA 5001, Australia
| | - E. Ali
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - C. G. Ning
- Department of Physics, State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China
| | - J. Colgan
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - O. Ingólfsson
- Science Institute and Department of Chemistry, University of Iceland, Dunhagi 3, 107 Reykjavík, Iceland
| | - D. H. Madison
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - M. J. Brunger
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide SA 5001, Australia
- Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
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13
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Jones DB, Ali E, Nixon KL, Limão-Vieira P, Hubin-Franskin MJ, Delwiche J, Ning CG, Colgan J, Murray AJ, Madison DH, Brunger MJ. Electron- and photon-impact ionization of furfural. J Chem Phys 2015; 143:184310. [DOI: 10.1063/1.4935444] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- D. B. Jones
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia
| | - E. Ali
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - K. L. Nixon
- Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
- School of Biology, Chemistry and Forensic Science, University of Wolverhampton, Wolverhampton WV1 1LY, United Kingdom
| | - P. Limão-Vieira
- Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - M.-J. Hubin-Franskin
- Départment de Chimie, Université de Liège, Institut de Chimie-Bât. B6C, B-4000 Liège 1, Belgium
| | - J. Delwiche
- Départment de Chimie, Université de Liège, Institut de Chimie-Bât. B6C, B-4000 Liège 1, Belgium
| | - C. G. Ning
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - J. Colgan
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - A. J. Murray
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - D. H. Madison
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - M. J. Brunger
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia
- Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
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da Silva GB, Neves RFC, Chiari L, Jones DB, Ali E, Madison DH, Ning CG, Nixon KL, Lopes MCA, Brunger MJ. Triply differential (e,2e) studies of phenol. J Chem Phys 2015; 141:124307. [PMID: 25273437 DOI: 10.1063/1.4896072] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
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.
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Affiliation(s)
- G B da Silva
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia
| | - R F C Neves
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia
| | - L Chiari
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia
| | - D B Jones
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia
| | - E Ali
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - D H Madison
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| | - C G Ning
- Department of Physics, State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China
| | - K L Nixon
- Departamento de Física, UFJF, Juiz de Fora, 36036-330, MG, Brazil
| | - M C A Lopes
- Departamento de Física, UFJF, Juiz de Fora, 36036-330, MG, Brazil
| | - M J Brunger
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia
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Morini F, Deleuze MS, Watanabe N, Takahashi M. Theoretical study of molecular vibrations in electron momentum spectroscopy experiments on furan: an analytical versus a molecular dynamical approach. J Chem Phys 2015; 142:094308. [PMID: 25747082 DOI: 10.1063/1.4913642] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The influence of thermally induced nuclear dynamics (molecular vibrations) in the initial electronic ground state on the valence orbital momentum profiles of furan has been theoretically investigated using two different approaches. The first of these approaches employs the principles of Born-Oppenheimer molecular dynamics, whereas the so-called harmonic analytical quantum mechanical approach resorts to an analytical decomposition of contributions arising from quantized harmonic vibrational eigenstates. In spite of their intrinsic differences, the two approaches enable consistent insights into the electron momentum distributions inferred from new measurements employing electron momentum spectroscopy and an electron impact energy of 1.2 keV. Both approaches point out in particular an appreciable influence of a few specific molecular vibrations of A1 symmetry on the 9a1 momentum profile, which can be unravelled from considerations on the symmetry characteristics of orbitals and their energy spacing.
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Affiliation(s)
- Filippo Morini
- Center of Molecular and Materials Modelling, Hasselt University, Agoralaan Gebouw D, B-3590 Diepenbeek, Belgium
| | - Michael S Deleuze
- Center of Molecular and Materials Modelling, Hasselt University, Agoralaan Gebouw D, B-3590 Diepenbeek, Belgium
| | - Noboru Watanabe
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
| | - Masahiko Takahashi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
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Builth-Williams JD, Bellm SM, Chiari L, Thorn PA, Jones DB, Chaluvadi H, Madison DH, Ning CG, Lohmann B, da Silva GB, Brunger MJ. A dynamical (e,2e) investigation of the structurally related cyclic ethers tetrahydrofuran, tetrahydropyran, and 1,4-dioxane. J Chem Phys 2013; 139:034306. [DOI: 10.1063/1.4813237] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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17
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Nixon KL, Murray AJ, Chaluvadi H, Ning C, Colgan J, Madison DH. Low energy (e,2e) coincidence studies of NH3: Results from experiment and theory. J Chem Phys 2013; 138:174304. [DOI: 10.1063/1.4802960] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Xu S, Chaluvadi H, Ren X, Pflüger T, Senftleben A, Ning CG, Yan S, Zhang P, Yang J, Ma X, Ullrich J, Madison DH, Dorn A. Low energy (e, 2e) study from the 1t2 orbital of CH4. J Chem Phys 2012; 137:024301. [DOI: 10.1063/1.4732539] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Bellm SM, Builth-Williams JD, Jones DB, Chaluvadi H, Madison DH, Ning CG, Wang F, Ma XG, Lohmann B, Brunger MJ. Dynamical (e,2e) studies of tetrahydrofurfuryl alcohol. J Chem Phys 2012; 136:244301. [DOI: 10.1063/1.4729466] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
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20
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Builth-Williams JD, Bellm SM, Jones DB, Chaluvadi H, Madison DH, Ning CG, Lohmann B, Brunger MJ. Experimental and theoretical investigation of the triple differential cross section for electron impact ionization of pyrimidine molecules. J Chem Phys 2012; 136:024304. [PMID: 22260576 DOI: 10.1063/1.3675167] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
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 7b(2) and 10a(1) 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.
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Affiliation(s)
- J D Builth-Williams
- ARC Centre of Excellence for Antimatter-Matter Studies, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia
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Nixon KL, Murray AJ, Chaluvadi H, Ning C, Madison DH. Low energy (e,2e) studies from CH4: Results from symmetric coplanar experiments and molecular three-body distorted wave theory. J Chem Phys 2011; 134:174304. [DOI: 10.1063/1.3581812] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Nixon KL, Murray AJ. Differential cross sections for ionization of laser-aligned atoms by electron impact. PHYSICAL REVIEW LETTERS 2011; 106:123201. [PMID: 21517314 DOI: 10.1103/physrevlett.106.123201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Indexed: 05/30/2023]
Abstract
The first experimental data are given for (e,2e) ionization from laser-aligned atoms. A linearly polarized laser excited Mg atoms to the 3¹P₁ state prior to ionization by low energy electrons. The scattered and ejected electrons were detected in coincidence and the differential cross section determined for a range of alignment angles. An asymmetric coplanar geometry was used, with one electron fixed and the other detected at different angles. The data are compared to that from the spherically symmetric 3¹S₀ state. Significant differences are found, in both magnitude and angular distribution.
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Affiliation(s)
- Kate L Nixon
- Photon Science Institute, School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom
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Colyer CJ, Bellm SM, Lohmann B, Hanne GF, Al-Hagan O, Madison DH, Ning CG. Dynamical (e, 2e) studies using tetrahydrofuran as a DNA analog. J Chem Phys 2010; 133:124302. [DOI: 10.1063/1.3491030] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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