Py3BR: A software for computing atomic three‐body recombination rates

• Published in: Journal of computational chemistry 2024-06, Vol.45 (17), p.1505-1514
• Main Authors: Koots, Rian, Wang, Yu, Mirahmadi, Marjan, Pérez‐Ríos, Jesús
• Format: Article
• Language: English
• Subjects: Classical Reaction Dynamics; Recombination coefficient; Recombination reactions; Software; Termolecular Reactions; Three‐Body Recombination
• ISSN: 0192-8651; 1096-987X
• DOI: 10.1002/jcc.27341

The three‐body recombination reaction, or ternary association, is a termolecular reaction leading to a molecule after a three‐body encounter that plays a vital role in many relevant scenarios in chemical physics. Here, we introduce the Python 3‐Body Recombination program, which is dedicated to the computation of atomic three‐body recombination rate coefficients. The software is based on a classical trajectory approach in hyperspherical coordinates after mapping the three‐body problem as a single particle in a higher‐dimensional space. This theoretical approach is fully general and applicable to any ion‐atom‐atom or atom‐atom‐atom three‐body process. The predictive power of the methodology has been tested in several different experimental scenarios, reaching a good description of every system. The code structure is presented alongside examples and tests to ensure the software's capacity. In addition, the performance of the software after parallelization is shown. Three‐body recombination reactions in which three free atoms collide to form a molecule and a free atom appear in a multitude of scenarios, from atmospheric phenomena to ultracold experiments. Python 3‐Body Recombination is a software for the classical simulation of direct three‐body recombination to further the limited theoretical understanding of these reactions.