# Low-energy elastic and inelastic scattering of electrons from SO{sub 2} using the R-matrix method

## Abstract

R-matrix method is used to calculate elastic differential, integral, and momentum transfer cross sections for electron-SO{sub 2} collision. The electron-impact excitation cross sections for first seven low-lying electronic excited states of SO{sub 2} molecule from the ground state of SO{sub 2} molecule have been calculated for the first time. Sixteen low-lying electronic states of SO{sub 2} molecule are included in the close coupling expansion of the wave function of the entire scattering system, which have vertical excitation energies up to 10.51 eV. Configuration-interaction (CI) wave functions are used to calculate these excitation energies. In our CI model, we keep the core 14 electrons frozen in doubly occupied molecular orbitals 1a{sub 1}, 2a{sub 1}, 3a{sub 1}, 4a{sub 1}, 1b{sub 1}, 1b{sub 2}, 2b{sub 2} and the remaining 18 electrons span the relevant active space: 5a{sub 1}, 6a{sub 1}, 7a{sub 1}, 8a{sub 1}, 9a{sub 1}, 2b{sub 1}, 3b{sub 1}, 3b{sub 2}, 4b{sub 2}, 5b{sub 2}, 6b{sub 2}, and 1a{sub 2}. Our calculated dipole moment of the ground state of SO{sub 2} at its equilibrium geometry is 0.79 a.u., which is in reasonable agreement with the corresponding experimental value 0.64 a.u. Our calculations detect one bound SO{sub 2}{sup -} state ({sup 2}B{sub 1})more »

- Authors:

- Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)

- Publication Date:

- OSTI Identifier:
- 20787101

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.73.042702; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 74 ATOMIC AND MOLECULAR PHYSICS; ANIONS; APPROXIMATIONS; BOUND STATE; CONFIGURATION INTERACTION; COUPLING; CROSS SECTIONS; DIPOLE MOMENTS; DISSOCIATION; ELECTRON ATTACHMENT; ELECTRON-MOLECULE COLLISIONS; ELECTRONS; EQUILIBRIUM; EV RANGE; EXCITATION; EXCITED STATES; GEOMETRY; GROUND STATES; INELASTIC SCATTERING; MOLECULAR STRUCTURE; MOLECULES; MOMENTUM TRANSFER; R MATRIX; RESONANCE; SULFUR DIOXIDE; WAVE FUNCTIONS

### Citation Formats

```
Gupta, Monika, and Baluja, K. L.
```*Low-energy elastic and inelastic scattering of electrons from SO{sub 2} using the R-matrix method*. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVA.73.0.

```
Gupta, Monika, & Baluja, K. L.
```*Low-energy elastic and inelastic scattering of electrons from SO{sub 2} using the R-matrix method*. United States. doi:10.1103/PHYSREVA.73.0.

```
Gupta, Monika, and Baluja, K. L. Sat .
"Low-energy elastic and inelastic scattering of electrons from SO{sub 2} using the R-matrix method". United States.
doi:10.1103/PHYSREVA.73.0.
```

```
@article{osti_20787101,
```

title = {Low-energy elastic and inelastic scattering of electrons from SO{sub 2} using the R-matrix method},

author = {Gupta, Monika and Baluja, K. L.},

abstractNote = {R-matrix method is used to calculate elastic differential, integral, and momentum transfer cross sections for electron-SO{sub 2} collision. The electron-impact excitation cross sections for first seven low-lying electronic excited states of SO{sub 2} molecule from the ground state of SO{sub 2} molecule have been calculated for the first time. Sixteen low-lying electronic states of SO{sub 2} molecule are included in the close coupling expansion of the wave function of the entire scattering system, which have vertical excitation energies up to 10.51 eV. Configuration-interaction (CI) wave functions are used to calculate these excitation energies. In our CI model, we keep the core 14 electrons frozen in doubly occupied molecular orbitals 1a{sub 1}, 2a{sub 1}, 3a{sub 1}, 4a{sub 1}, 1b{sub 1}, 1b{sub 2}, 2b{sub 2} and the remaining 18 electrons span the relevant active space: 5a{sub 1}, 6a{sub 1}, 7a{sub 1}, 8a{sub 1}, 9a{sub 1}, 2b{sub 1}, 3b{sub 1}, 3b{sub 2}, 4b{sub 2}, 5b{sub 2}, 6b{sub 2}, and 1a{sub 2}. Our calculated dipole moment of the ground state of SO{sub 2} at its equilibrium geometry is 0.79 a.u., which is in reasonable agreement with the corresponding experimental value 0.64 a.u. Our calculations detect one bound SO{sub 2}{sup -} state ({sup 2}B{sub 1}) at the equilibrium geometry of SO{sub 2} molecule. Both shape as well as core-excited shape resonances have been identified in the present work and are correlated with the experimental results on dissociative electron attachment study. A detailed analysis of resonances is provided. Cross sections are reported for the electron impact energy range 0-15 eV. All cross section calculations are performed in the fixed-nuclei approximation at the experimental equilibrium geometry of the ground state of SO{sub 2} molecule. We have also investigated dependence of resonances on the geometry of SO{sub 2} molecule to probe the possible pathways for dissociation of resulting negative ion upon electron attachment. We have excellent agreement of differential, elastic integral, and momentum transfer cross sections calculated in the 16-state R-matrix approximation with the available experimental results for electron-impact energy range 0-15 eV. Our resonant peaks correlate well with the peaks observed in the study of dissociative electron attachment (DEA) of electron with SO{sub 2} molecule.},

doi = {10.1103/PHYSREVA.73.0},

journal = {Physical Review. A},

number = 4,

volume = 73,

place = {United States},

year = {Sat Apr 15 00:00:00 EDT 2006},

month = {Sat Apr 15 00:00:00 EDT 2006}

}