PyQCAMS: Python Quasi-Classical Atom-Molecule Scattering

Abstract

We present Python Quasi-classical atom-molecule scattering (PyQCAMS), a new Python package for atom-molecule scattering within the quasi-classical trajectory approach. The input consists of mass, collision energy, impact parameter, and pair-wise interactions to choose between Buckingham, generalized Lennard-Jones, and Morse potentials. As the output, the code provides the vibrational quenching, dissociation, and reactive cross sections along with the rovibrational energy distribution of the reaction products. Furthermore, we treat H$_2$ + Ca $\rightarrow$ CaH + H reactions as a prototypical example to illustrate the properties and performance of the software. Finally, we study the parallelization performance of the code by looking into the time per trajectory as a function of the number of CPUs used.