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Full-Text Articles in Physics
Machine Learning Corrected Quantum Dynamics Calculations, A. Jasinski, J. Montaner, R. C. Forrey, B. H. Yang, P. C. Stancil, Naduvalath Balakrishnan, J. Dai, A. Vargas-Hernandez, R. V. Krems
Machine Learning Corrected Quantum Dynamics Calculations, A. Jasinski, J. Montaner, R. C. Forrey, B. H. Yang, P. C. Stancil, Naduvalath Balakrishnan, J. Dai, A. Vargas-Hernandez, R. V. Krems
Chemistry and Biochemistry Faculty Research
Quantum scattering calculations for all but low-dimensional systems at low energies must rely on approximations. All approximations introduce errors. The impact of these errors is often difficult to assess because they depend on the Hamiltonian parameters and the particular observable under study. Here, we illustrate a general, system- and approximation-independent, approach to improve the accuracy of quantum dynamics approximations. The method is based on a Bayesian machine learning (BML) algorithm that is trained by a small number of exact results and a large number of approximate calculations, resulting in ML models that can generalize exact quantum results to different dynamical …
Non-Adiabatic Quantum Dynamics Of The Ultracold Li+Lina→ Li2+Na Chemical Reaction, B. K. Kendrick, M. Li, H. Li, S. Kotochigova, J. F.E. Croft, Balakrishnan Naduvalath
Non-Adiabatic Quantum Dynamics Of The Ultracold Li+Lina→ Li2+Na Chemical Reaction, B. K. Kendrick, M. Li, H. Li, S. Kotochigova, J. F.E. Croft, Balakrishnan Naduvalath
Chemistry and Biochemistry Faculty Research
We report non-adiabatic dynamics of the Li+LiNa→Li2+Na chemical reaction at cold and ultracold temperatures employing accurate ab initio electronic potential energy surfaces in a quantum dynamics formulation employing a diabatic representation. Results are compared against those from a single adiabatic ground state potential energy surface and a universal model based on the long-range interaction potential. We discuss signatures of non-universal behavior in the total rate coefficients as well as strong non-adiabatic effects in the state-to-state rotationally resolved rate coefficients.
Stereodynamical Control Of A Quantum Scattering Resonance In Cold Molecular Collisions, Pablo G. Jambrina, James F.E. Croft, Hua Guo, Mark Brouard, Balakrishnan Naduvalath, F. Javier Aoiz
Stereodynamical Control Of A Quantum Scattering Resonance In Cold Molecular Collisions, Pablo G. Jambrina, James F.E. Croft, Hua Guo, Mark Brouard, Balakrishnan Naduvalath, F. Javier Aoiz
Chemistry and Biochemistry Faculty Research
Cold collisions of light molecules are often dominated by a single partial wave resonance. For the rotational quenching of HD (v=1, j=2) by collisions with ground state para-H2, the process is dominated by a single L=2 partial wave resonance centered around 0.1 K. Here, we show that this resonance can be switched on or off simply by appropriate alignment of the HD rotational angular momentum relative to the initial velocity vector, thereby enabling complete control of the collision outcome.