| Full text | |
| Author(s): |
Jones, D. B.
[1]
;
Blanco, F.
[2]
;
Garcia, G.
[3]
;
da Costa, R. F.
[4, 5]
;
Kossoski, F.
[4]
;
Varella, M. T. do N.
[6]
;
Bettega, M. H. F.
[7]
;
Lima, M. A. P.
[4]
;
White, R. D.
[8]
;
Brunger, M. J.
[1]
Total Authors: 10
|
| Affiliation: | [1] Flinders Univ S Australia, Coll Sci & Engn, GPO Box 2100, Adelaide, SA 5001 - Australia
[2] Univ Complutense Madrid, Dept Fis Atom Mol & Nucl, E-28040 Madrid - Spain
[3] CSIC, Inst Fis Fundamental, Serano 113 Bis, E-28006 Madrid - Spain
[4] Univ Estadual Campinas, Inst Fis Gleb Wataghin, Campinas, SP - Brazil
[5] Univ Fed Espirito Santo, Dept Fis, Ctr Ciencias Exatas, BR-29075901 Vitoria, ES - Brazil
[6] Univ Sao Paulo, Inst Fis, Rua Matao 1731, BR-05508090 Sao Paulo - Brazil
[7] Univ Fed Parana, Dept Fis, CP 19044, BR-81531990 Curitiba, Parana - Brazil
[8] James Cook Univ, Coll Sci & Engn, Townsville, Qld 4811 - Australia
Total Affiliations: 8
|
| Document type: | Journal article |
| Source: | Journal of Chemical Physics; v. 147, n. 24 DEC 28 2017. |
| Web of Science Citations: | 6 |
| Abstract | |
We report on theoretical elastic and experimental vibrational-excitation differential cross sections (DCSs) for electron scattering from para-benzoquinone (C6H4O2), in the intermediate energy range 15-50 eV. The calculations were conducted with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that also now incorporates a further interference (I) term. The SMCPP with N energetically open electronic states (N-open) at the static-exchange-plus-polarisation (N(open)ch-SEP) level was used to calculate the scattering amplitudes using a channel coupling scheme that ranges from 1ch-SE up to the 89ch-SEP level of approximation. We found that in going from the 38ch-SEP to the 89ch-SEP, at all energies considered here, the elastic DCSs did not change significantly in terms of both their shapes and magnitudes. This is a good indication that our SMCPP 89ch-SEP elastic DCSs are converged with respect to the multichannel coupling effect for the investigated intermediate energies. While agreement between our IAM-SCAR+I and SMCPP 89ch-SEP computations improves as the incident electron energy increases from 15 eV, overall the level of accord is only marginal. This is particularly true at middle scattering angles, suggesting that our SCAR and interference corrections are failing somewhat for this molecule below 50 eV. We also report experimental DCS results, using a crossed-beam apparatus, for excitation of some of the unresolved ({''}hybrid{''}) vibrational quanta (bands I-III) of para-benzoquinone. Those data were derived from electron energy loss spectra that were measured over a scattered electron angular range of 10 degrees-90 degrees and put on an absolute scale using our elastic SMCPP 89ch-SEP DCS results. The energy resolution of our measurements was similar to 80 meV, which is why, at least in part, the observed vibrational features were only partially resolved. To the best of our knowledge, there are no other experimental or theoretical vibrational excitation results against which we might compare the present measurements. Published by AIP Publishing. (AU) | |
| FAPESP's process: | 14/10012-9 - Molecular transients |
| Grantee: | Márcio Teixeira do Nascimento Varella |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 15/23792-5 - Semiclassical non-adiabatic dynamics of transient anions |
| Grantee: | Fábris Kossoski |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |