# Quantemol Electron Collisions (QEC): An Enhanced Expert System for Performing Electron Molecule Collision Calculations Using the R-Matrix Method

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## Abstract

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## 1. Introduction

## 2. The R-Matrix Method

## 3. The QEC Interface

## 4. Concluding Remarks

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 1.**Screenshot of the molecular set-up page in the Quantemol Electron Collision (QEC) graphical user interface (GUI) showing methane as an example. The screenshot was taken after the geometry had been optimized using Molpro and the coordinates automatically shifted to the center of mass.

**Figure 2.**Screenshot of the page in the QEC GUI which sets up the molecular target calculation which is performed using Molpro.

**Figure 3.**Screenshot of the page in the QEC GUI which set the parameters for the scattering calculation.

**Figure 4.**Sample screen for a close-coupling (CC) calculation on methane showing the outputs selected to be total cross section, the eigenphase sums for each symmetry, the rate of elastic scattering as a function of temperature and the ionization cross section computed using the binary encounter Bethe (BEB) method.

**Figure 5.**Examples of graphical outputs produced by QEC for a static exchange (SE) calculation on methane showing total cross sections, eigenphase sums, rates and ionization (BEB) cross sections.

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**MDPI and ACS Style**

Cooper, B.; Tudorovskaya, M.; Mohr, S.; O’Hare, A.; Hanicinec, M.; Dzarasova, A.; Gorfinkiel, J.D.; Benda, J.; Mašín, Z.; Al-Refaie, A.F.; Knowles, P.J.; Tennyson, J. Quantemol Electron Collisions (QEC): An Enhanced Expert System for Performing Electron Molecule Collision Calculations Using the R-Matrix Method. *Atoms* **2019**, *7*, 97.
https://doi.org/10.3390/atoms7040097

**AMA Style**

Cooper B, Tudorovskaya M, Mohr S, O’Hare A, Hanicinec M, Dzarasova A, Gorfinkiel JD, Benda J, Mašín Z, Al-Refaie AF, Knowles PJ, Tennyson J. Quantemol Electron Collisions (QEC): An Enhanced Expert System for Performing Electron Molecule Collision Calculations Using the R-Matrix Method. *Atoms*. 2019; 7(4):97.
https://doi.org/10.3390/atoms7040097

**Chicago/Turabian Style**

Cooper, Bridgette, Maria Tudorovskaya, Sebastian Mohr, Aran O’Hare, Martin Hanicinec, Anna Dzarasova, Jimena D. Gorfinkiel, Jakub Benda, Zdeněk Mašín, Ahmed F. Al-Refaie, Peter J. Knowles, and Jonathan Tennyson. 2019. "Quantemol Electron Collisions (QEC): An Enhanced Expert System for Performing Electron Molecule Collision Calculations Using the R-Matrix Method" *Atoms* 7, no. 4: 97.
https://doi.org/10.3390/atoms7040097