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Integral cross sections for optically allowed electronic-state excitations by electron impact, are reviewed for polyatomic molecules by applying the Binary-Encounter-Bethe (BEB) scaling model. Following the context of the present review, the scaling model originally proposed by Yong-Ki Kim to determine electron-impact cross sections for ionization of atoms and molecules is also summarized briefly for its wide range of applications [Electron-Impact Cross Section Database, NIST, Y.-K. Kim][1]. The present report not only focuses on the need for the cross-section data, but also elucidates the verification of the scaling model in the general application for atoms and molecules. Since this report is for a data base, it is summarized for data base users by citing (copying) the descriptions in the original papers and the references within those papers in the style of a textbook.

© American Institute of Physics. M.C.A.L. acknowledges financial support from Brazilian Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Fundacao de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG), and FINEP, while M.J.B. thanks CNPq for his “Special Visiting Professor” award. Some financial assistance from the Australian Research Council through Grant No. DP160102787 is also noted. Finally, S. Ghosh acknowledges for his grant from PNPD/CAPES, while G. Garcia thanks the Spanish Ministerio de Economia, Industria y Competitividad for his project Grant No. FIS 2016-80440 and the EU Project No. FP7–ITN–ARGENT-608163., Absolute total cross section (TCS) measurements for electron scattering from 1-propanol molecules are reported for impact energies from 40 to 500 eV. These measurements were obtained using a new apparatus developed at Juiz de Fora Federal University-Brazil, which is based on the measurement of the attenuation of a collimated electron beam through a gas cell containing the molecules to be studied at a given pressure. Besides these experimental measurements, we have also calculated TCS using the Independent-Atom Model with Screening Corrected Additivity Rule and Interference (IAM-SCAR+I) approach with the level of agreement between them being typically found to be very good. Published by AIP Publishing., Unión Europea. FP7, Ministerio de Economía y Competitividad (MINECO), Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Fundacao de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG), FINEP, CNPq, Australian Research Council, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

Integral cross sections for optically allowed electronic-state excitations by electron impact, are reviewed for polyatomic molecules by applying the Binary-Encounter-Bethe (BEB) scaling model. Following the context of the present review, the scaling model originally proposed by Yong-Ki Kim to determine electron-impact cross sections for ionization of atoms and molecules is also summarized briefly for its wide range of applications [Electron-Impact Cross Section Database, NIST, Y.-K. Kim][1]. The present report not only focuses on the need for the cross-section data, but also elucidates the verification of the scaling model in the general application for atoms and molecules. Since this report is for a data base, it is summarized for data base users by citing (copying) the descriptions in the original papers and the references within those papers in the style of a textbook.

We report the results of measurements and calculations for elastic electron scattering from 3-hydroxytetrahydrofuran (C4H8O2). The measurements are performed with a crossed electron-target beam apparatus and the absolute cross-sections are determined using the relative flow technique. The calculations are carried out using the Schwinger multichannel method in the static-exchange plus polarization (SEP) approximation. A set of angular differential cross-sections (DCS) is provided at five incident energies (6.5, 8, 10, 15 and 20 eV) over an angular range of 20–130°, and the energy dependence of the elastic DCS at a scattering angle of 120° is also presented. Integral elastic and elastic momentum transfer cross-sections have also been derived and calculated. The results are compared with those of recent measurements and calculations for the structurally similar molecule tetrahydrofuran (C4H8O).

We report the results of measurements and calculations for elastic electron scattering from 3-hydroxytetrahydrofuran (C4H8O2). The measurements are performed with a crossed electron-target beam apparatus and the absolute cross-sections are determined using the relative flow technique. The calculations are carried out using the Schwinger multichannel method in the static-exchange plus polarization (SEP) approximation. A set of angular differential cross-sections (DCS) is provided at five incident energies (6.5, 8, 10, 15 and 20 eV) over an angular range of 20–130°, and the energy dependence of the elastic DCS at a scattering angle of 120° is also presented. Integral elastic and elastic momentum transfer cross-sections have also been derived and calculated. The results are compared with those of recent measurements and calculations for the structurally similar molecule tetrahydrofuran (C4H8O).

Final measurements are reported for the production of free-free emission by low energy electrons in argon. Absolute intensity measurements were made at 500, 650 and 1300 nm. The electric field to gas density ratio was varied from 0.25 to 10 x 10 to the minus 21st power Vm2 corresponding to mean electron energies from 1.2 to 5.4 eV. The experimental results agree well with theoretical values calculated from cross sections for momentum transfer collisions determined by other techniques. Measurements of vibrational excitation of 02, H2 and D2 were initiated using the collisional transfer of energy from a homonuclear molecule to a heteronuclear molecule, i.e. CS2 for 02 and C02 or C0 for H2 and D2. Signals were observed using D2 and C02.

Measurements and analyses are reported for the vibrational excitation of D2 and H2 by low and moderate energy electrons. The measurements were made using the electron drift tube technique. The vibrationally excited D2 and H2 are detected by the transfer of excitation to CO or CO2 and the measurement of the intensity of 4.7 micrometer or 4.3 micrometer infrared emission. The derived cross sections for the vibrational excitation of D2 are significantly smaller than the corresponding cross sections for H2. Apparatus has been constructed and tested for the measurement of the density of excited H2 in the c3 Pi metastable state by laser induced fluorescence and laser absorption techniques. (Author)