Abstract
We have calculated ground state interaction energies for an antihydrogen atom and a hydrogen molecule within the Born-Oppenheimer approximation. Leptonic energies were calculated using a large basis set of explicitly correlated Gaussian functions. Energies were calculated at over 2800 geometries including different proton-proton distances. The energies have been fit to functional forms using a neural network for the short-range interaction which is combined with asymptotic formulas at long range. A two-dimensional rigid rotor and a three-dimensional atom-molecule potential energy surface (PES) have been determined. Rigid-rotor scattering calculations on these surfaces have been carried out using the S-matrix Kohn variational method with a two-dimensional Gaussian basis set. We have calculated cross sections for elastic, rotationally inelastic and annihilation collisions on the two-dimensional PES. This includes the first calculation of leptonic annihilation for this system.
Original language | English |
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Article number | 185201 |
Number of pages | 14 |
Journal | Journal of Physics B: Atomic, Molecular and Optical Physics |
Volume | 52 |
Issue number | 18 |
Early online date | 23 Aug 2019 |
DOIs | |
Publication status | Published - 28 Sept 2019 |
Bibliographical note
We are grateful for helpful discussions with Edward Armour, Martin Plummer and Gleb Gribakin. This work was supported by the UK Engineering and Physical Sciences Research Council (EPSRC) via a Doctoral Training Account studentship for BPM, grant number EP/K502960/1. The contribution of KS was financed by the statutory activity subsidy from the Polish Ministry of Science and Higher Education for the Faculty of Chemistry of Wrocław University of Science and Technology (contract number 0401/0121/18). We thank the EPSRC-funded CCPQ consortium and the Royal Society of Chemistry for further financial support. We also thank the referees for their comments on the manuscript.Keywords
- antihydrogen
- matter-antimatter interactions
- low energy scattering
- potential energy surface
- elastic scattering
- inelastic scattering
- annihilation
- CORRELATED GAUSSIAN FUNCTIONS
- S-MATRIX VERSION
- VARIATIONAL CALCULATIONS
- TRIATOMIC-MOLECULES
- GROUND-STATE
- HE
- DYNAMICS
- SYSTEMS
- CHARGE