Felipe Arretche , Eliton P. Seidel , Wagner Tenfen
{"title":"A semiempirical model for low energy electron–atom transport cross sections: The case of noble gases","authors":"Felipe Arretche , Eliton P. Seidel , Wagner Tenfen","doi":"10.1016/j.elspec.2024.147476","DOIUrl":"10.1016/j.elspec.2024.147476","url":null,"abstract":"<div><p>A semiempirical approach to describe low energy electron–atom transport cross sections of easy implementation and reproduction is presented. The heart of the model is an energy independent two-parameter potential that was adjusted to reproduce the accurate total cross sections for He, Ne, Ar and Kr, measured with a threshold photoelectron source technique from meV up to 20 eV. Once the potential was conceived, the model was validated by comparing the values obtained for the calculated scattering lengths and phase shifts with the respective quantities previously reported in the literature. We close the article by presenting the momentum transfer and viscosity cross sections. Good agreement is found when compared to the similar data obtained from swarm experiments, from phase shifts according to differential cross section measurements and to the cross sections reported by sophisticated <em>ab initio</em> relativistic many-body calculations. Tables for the phase shifts and cross sections are provided for direct use and applications.</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"275 ","pages":"Article 147476"},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142098470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhuocheng Xu , Xinyi Hao , Yuting Dai , Christian Kübel , Milo S.P. Shaffer , Benjamin Watts , Qianqian Li
{"title":"Synchrotron scanning transmission x-ray spectro-microscopy (STXM) characterisation of β-SiC nanowhisker AZ91 magnesium alloy nanocomposites","authors":"Zhuocheng Xu , Xinyi Hao , Yuting Dai , Christian Kübel , Milo S.P. Shaffer , Benjamin Watts , Qianqian Li","doi":"10.1016/j.elspec.2024.147477","DOIUrl":"10.1016/j.elspec.2024.147477","url":null,"abstract":"<div><p>β-SiC nanoparticles are one of the most common reinforcements in Mg-Al alloy matrix nanocomposites (MgMNCs). The interfacial interactions between β-SiC and the alloy matrix are complex due to the occurrence of new phases and the fine scale of the 3D architecture. This study aims to explore the feasibility of using synchrotron Scanning Transmission X-ray spectro-Microscopy (STXM) to investigate such interfacial interactions and acquire reference X-ray Absorption Spectroscopy (XAS) data for some common interphase crystals present within the composites, which are not readily available. Throughout this study, a reliable procedure for collecting STXM data on samples derived from MgMNCs was developed, and reference XAS spectra for α-Mg, β-Mg<sub>17</sub>Al<sub>12</sub>, T2-Al<sub>2</sub>MgC<sub>2</sub>, Mg<sub>2</sub>Si and MgO present in MgMNCs were collected. The accessibility of STXM and spatially resolved XAS spectrum is not only useful for nanocomposite alloy research but applicable widely across the magnesium alloy research community when identifying and quantifying the phases with complex crystal structures and oxide states.</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"276 ","pages":"Article 147477"},"PeriodicalIF":1.8,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0368204824000604/pdfft?md5=cf5a99b62862d53eb59335e8679447e9&pid=1-s2.0-S0368204824000604-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142151392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electronic structure of peroxide-based explosives","authors":"Igor Novak","doi":"10.1016/j.elspec.2024.147475","DOIUrl":"10.1016/j.elspec.2024.147475","url":null,"abstract":"<div><p>The vertical, valence ionization energies for three peroxide based explosives: triacetone triperoxide (TATP), hexamethylene triperoxide diamine (HMTD) and diacetone diperoxide (DADP) have been calculated (as free molecules) using high-level ab initio coupled-cluster method: IP-EOM-CCSD. The calculated vertical, valence ionization energies were used to simulate UV photoelectron spectra. Our results, especially 1st ionization energies are discussed together compared with previous results on adiabatic energies. The variations of vertical ionization energies were rationalized by the analysis of the electronic structure of PBEs. The valence electronic structures depend on the number, type and position of peroxide groups. HOMO-LUMO gaps and the influence of electronic structures on explosive properties were also discussed.</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"275 ","pages":"Article 147475"},"PeriodicalIF":1.8,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0368204824000586/pdfft?md5=d6b06a07ae7ebe842d13471d945fb04f&pid=1-s2.0-S0368204824000586-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141998622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"I4P: An Igor Pro suite for photoemission analysis","authors":"Rémi Lazzari","doi":"10.1016/j.elspec.2024.147474","DOIUrl":"10.1016/j.elspec.2024.147474","url":null,"abstract":"<div><p>A package based on the <em>Igor Pro</em> scripting language is proposed for the analysis of photoemission spectroscopy data (XPS, HAXPES, UPS). Compared to the already numerous available softwares, the <em>Igor Pro Paris Photoemission Package (I4P)</em> gathers in a single tool: (i) basic data analysis and plotting features (such as satellite/ghost line deconvolution, inelastic background subtraction, determination of the intensity-energy response function and its correction, peak overlap, energy-mass conversion in ion scattering spectroscopy), (ii) databases of binding energies, of photo-ionization cross sections, of inelastic/transport mean free paths and effective attenuation lengths, (iii) quantification based on elastic peak areas accounting for elastic scattering, (iv) depth profiling by angle-resolved photoemission and by inelastic background analysis, (iv) peak fitting with 17 different line shapes including background and fully configurable constraints between fit parameters. Aside a detailed manual including the references to the relevant literature, <em>I4P</em> comes not only with a graphical interface but also with scripting commands. Most of all, the free availability of the source code allows the potential user to easily develop additional options of data treatment.</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"275 ","pages":"Article 147474"},"PeriodicalIF":1.8,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141851597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Mistry, A. Haque, B. Mandal, M. Mondal, S. Halder, M. Purkait
{"title":"State selective total and angular differential cross sections for positronium formation in e+−He collisions","authors":"T. Mistry, A. Haque, B. Mandal, M. Mondal, S. Halder, M. Purkait","doi":"10.1016/j.elspec.2024.147470","DOIUrl":"10.1016/j.elspec.2024.147470","url":null,"abstract":"<div><p>State-selective total and angular differential cross sections for positronium formation are presented in the collision of positron with helium atoms in their ground state by using the four-body formalism of the boundary-corrected continuum-intermediate-states approximation. The main purpose of the present study is to investigate the relative importance of intermediate ionization continuum states that has been incorporated with a suitable choice of distorting potential. In addition, the nine-dimensional integrals of the transition amplitude are analytically reduced to a one-dimensional real integral, which can be easily calculated numerically. The influence of the target static electron correlations on the capture probability is investigated using the different bound-state wave functions of He. The theoretical model for the calculation is fairly accurate and predicts a number of interesting features of the state-selective total and differential cross sections in the range of positron impact energy varies from 20 to <span><math><mrow><mn>250</mn><mspace></mspace><mi>eV</mi></mrow></math></span>. The total cross sections are highly peaked at an impact energy of 50 eV. The results are compared with those of other theories and the available experimental data. The present theoretical results and other measurements show satisfactory agreement in the wide energy range. Moreover, surface plots for the state-selective differential cross sections are also presented to illustrate the interesting feature of the positronium formation in this collision process.</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"275 ","pages":"Article 147470"},"PeriodicalIF":1.8,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141844225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Zidi , A. Kahoul , J.P. Marques , S. Daoudi , J.M. Sampaio , F. Parente , A. Hamidani , S. Croft , A. Favalli , Y. Kasri , K. Amari , B. Berkani
{"title":"Investigating empirical and theoretical calculations for intensity ratios of L-Shell X-ray transitions in atoms with 39 ≤ Z ≤ 94","authors":"A. Zidi , A. Kahoul , J.P. Marques , S. Daoudi , J.M. Sampaio , F. Parente , A. Hamidani , S. Croft , A. Favalli , Y. Kasri , K. Amari , B. Berkani","doi":"10.1016/j.elspec.2024.147473","DOIUrl":"10.1016/j.elspec.2024.147473","url":null,"abstract":"<div><p>The significance of theoretical, experimental, and analytical methods in calculating the intensity ratios of L-shell transitions for diverse elements lies in their widespread applications across various domains, including physical chemistry and medical research. In the present paper, empirical values for intensity ratios were computed through polynomial interpolations using experimental databases within the scope of atomic number 39 ≤ <em>Z</em> ≤ 92 for <span><math><mfrac><mrow><msub><mrow><mi>I</mi></mrow><mrow><mi>L</mi><mi>β</mi></mrow></msub></mrow><mrow><msub><mrow><mi>I</mi></mrow><mrow><mi>L</mi><mi>α</mi></mrow></msub></mrow></mfrac></math></span> and <span><math><mfrac><mrow><msub><mrow><mi>I</mi></mrow><mrow><mi>L</mi><mi>γ</mi></mrow></msub></mrow><mrow><msub><mrow><mi>I</mi></mrow><mrow><mi>L</mi><mi>α</mi></mrow></msub></mrow></mfrac></math></span>, and extending to the range of 39 ≤ <em>Z</em> ≤ 94 for <span><math><mfrac><mrow><msub><mrow><mi>I</mi></mrow><mrow><mi>Ll</mi></mrow></msub></mrow><mrow><msub><mrow><mi>I</mi></mrow><mrow><mi>L</mi><mi>α</mi></mrow></msub></mrow></mfrac></math></span>. Additionally, new theoretical calculations were conducted using the Multiconfiguration Dirac–Fock Method for specific elements. The obtained results were compared with standard theoretical, experimental, and empirical values, showing a reasonable agreement with them.</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"275 ","pages":"Article 147473"},"PeriodicalIF":1.8,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141775047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ivan Shcherba , Volodymyr Babizhetskyy , Victor N. Antonov , Henryk Noga , Olha Zhak , Lev Bekenov , Jürgen Köhler , Reinhard K. Kremer , Bogdan Kuzhel , Marcin Jasinski
{"title":"Intermediate valence behavior of the ternary cerium-nickel-phosphide Ce2Ni12P5","authors":"Ivan Shcherba , Volodymyr Babizhetskyy , Victor N. Antonov , Henryk Noga , Olha Zhak , Lev Bekenov , Jürgen Köhler , Reinhard K. Kremer , Bogdan Kuzhel , Marcin Jasinski","doi":"10.1016/j.elspec.2024.147471","DOIUrl":"10.1016/j.elspec.2024.147471","url":null,"abstract":"<div><p>The crystal structure of the ternary phosphide Ce<sub>2</sub>Ni<sub>12</sub>P<sub>5</sub> (La<sub>2</sub>Ni<sub>12</sub>P<sub>5</sub>-type structure) has been determined from X-ray powder diffraction data: full profile refinement, monoclinic symmetry, space group <em>P</em>2<sub>1</sub>/<em>m</em>, <em>a</em> = 10.7809(2) Å, <em>b</em> = 3.6869(1) Å, <em>c</em> = 13.1490(3) Å, <em>β</em> = 107.776(4)º, <em>R</em><sub>I</sub> = 0.068, <em>R</em><sub>P</sub> = 0.044, <em>R</em><sub>wP</sub> = 0.060. Ce<sub>2</sub>Ni<sub>12</sub>P<sub>5</sub> is a ferromagnet with a Curie temperature of 5.8(5) K. A significant deviation from the linearity of the temperature dependence of the electrical resistance for Ce<sub>2</sub>Ni<sub>12</sub>P<sub>5</sub> has been found. The low-temperature part of the electrical resistance indicates the presence of magnetic interactions in Ce<sub>2</sub>Ni<sub>12</sub>P<sub>5</sub>. The influence of a magnetic field on the electrical resistance of Ce<sub>2</sub>Ni<sub>12</sub>P<sub>5</sub> has been studied. The X-ray absorption spectrum at the Ce L<sub>III</sub> edge and X-ray emission spectra of Ni and P at the K and L<sub>III</sub> edges have been studied experimentally and theoretically using DFT+<em>U</em> calculations. The calculations show good agreement with the experimental measurements. The effective valence of Ce in Ce<sub>2</sub>Ni<sub>12</sub>P<sub>5</sub> determined based on the Ce L<sub>III</sub> absorption spectrum is <em>ϑ</em><sub>eff</sub> ∼ 3.05.</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"275 ","pages":"Article 147471"},"PeriodicalIF":1.8,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141736592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alexander P. Chaynikov , Andrei G. Kochur , Aleksey I. Dudenko
{"title":"Cascade energy reemission by the silver atom ionized by 0.01–100 keV photons. Possible application of silver-based radiosensitizing agents in photon beam radiation therapy","authors":"Alexander P. Chaynikov , Andrei G. Kochur , Aleksey I. Dudenko","doi":"10.1016/j.elspec.2024.147472","DOIUrl":"10.1016/j.elspec.2024.147472","url":null,"abstract":"<div><p>A method of straightforward construction and analysis of the cascade decay trees is applied to study the cascade energy reemission by silver atoms upon photoionization in the incident photon energy range of 0.01–100 keV. Cascade electrons and photons emitted during the cascade relaxation of an inner-shell vacancy carry away a significant part of the energy initially acquired by the silver atom in a photoionization act. The energies redistributed through following channels were calculated as functions of incident photon energy: energy absorbed by the silver atom itself (<em>a</em>), and energies carried away by the cascade electrons (<em>b</em>) and photons (<em>c</em>). Channel (<em>a</em>) is dominant only at small incident photon energies up to the <em>M</em><sub>5</sub> ionization threshold. Channel (<em>b</em>) dominates between <em>M</em> and <em>K</em> thresholds making 57–85 % of the acquired energy. Above the <em>K</em> threshold, the weight of channel (<em>b</em>) is still significant, 24 %, however, dominant is channel (<em>c</em>).</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"275 ","pages":"Article 147472"},"PeriodicalIF":1.8,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141775107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ivar Kuusik , Mati Kook , Tanel Käämbre , Georgia Michailoudi , Arvo Tõnisoo , Vambola Kisand , Rainer Pärna
{"title":"Gas-phase PES and GW investigation of two widespread herbicides: MCPA and 2,4-dichlorophenoxyacetic acid","authors":"Ivar Kuusik , Mati Kook , Tanel Käämbre , Georgia Michailoudi , Arvo Tõnisoo , Vambola Kisand , Rainer Pärna","doi":"10.1016/j.elspec.2024.147462","DOIUrl":"10.1016/j.elspec.2024.147462","url":null,"abstract":"<div><p>Photoelectron spectroscopy (PES) investigation of two widely used herbicide compounds MCPA and 2,4-D is reported. The GW calculations are shown to offer a good description of their electronic structure. There is excellent agreement between the experimental and theoretical energies of the HOMO states of 2,4-D and MCPA, which are at 8.7 eV and 8.5 eV binding energy, respectively. The low energy tail of the HOMO state extends to about 8 eV. The good agreement between the UPS (ultraviolet photoelectron spectroscopy) spectra and the simulation validates the proposed conformer. The presented gas phase data will help researchers to analyze data from liquid and diluted samples of these herbicide molecules and perform additional theoretical modelling.</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"275 ","pages":"Article 147462"},"PeriodicalIF":1.8,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141623664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Pacé , D. Gupta , T. Ferté , M. Riepp , G. Malinowski , M. Hehn , F. Pressacco , M. Silly , F. Sirotti , C. Boeglin , N. Bergeard
{"title":"Laser induced ultrafast Gd 4f spin dynamics at the surface of amorphous CoxGd100-x ferrimagnetic alloys","authors":"M. Pacé , D. Gupta , T. Ferté , M. Riepp , G. Malinowski , M. Hehn , F. Pressacco , M. Silly , F. Sirotti , C. Boeglin , N. Bergeard","doi":"10.1016/j.elspec.2024.147461","DOIUrl":"10.1016/j.elspec.2024.147461","url":null,"abstract":"<div><p>We have investigated the laser induced ultrafast dynamics of Gd 4f spins at the surface of Co<sub>x</sub>Gd<sub>100-x</sub> alloys by means of surface-sensitive and time-resolved dichroic resonant Auger spectroscopy. We have observed that the laser induced quenching of Gd 4f magnetic order at the surface of the Co<sub>x</sub>Gd<sub>100-x</sub> alloys occur on a much longer time scale than that previously reported in “bulk sensitive” time-resolved experiments. In parallel, we have characterized the static structural and magnetic properties at the surface and in the bulk of these alloys by combining Physical Property Measurement System (PPMS) magnetometry with X-ray Magnetic Circular Dichroism in absorption spectroscopy (XMCD) and X-Ray Photoelectron spectroscopy (XPS). The PPMS and XMCD measurements give information regarding the composition in the bulk of the alloys. The XPS measurements show non-homogeneous composition at the surface of the alloys with a strongly increased Gd content within the first layers compared to the nominal bulk values. Such larger Gd concentration results in a reduced indirect Gd 4f spin-lattice coupling. It explains the “slower” Gd 4f demagnetization we have observed in our surface-sensitive and time-resolved measurements compared to that previously reported by “bulk-sensitive” measurements.</p></div>","PeriodicalId":15726,"journal":{"name":"Journal of Electron Spectroscopy and Related Phenomena","volume":"275 ","pages":"Article 147461"},"PeriodicalIF":1.8,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141775048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}