A Nonorthogonal coordinate approach to atom-diatom parallel reactive scattering calculations

Computational approaches to the evaluation of the reactive scattering properties of atom-diatom reactions are revisited. The aim is to exploit both the use of nonorthogonal coordinates in reactive scattering and the restructuring of related computer codes for concurrent computing. To this end, bond length, bond-order and hyperspherical bond order coordinate formalisms are examined for the collinear case. At the same time, the evolution of parallel models from coarse to fine granularity and the development of parallelization supports from directive libraries to programming environments are discussed. The scalability of related codes is tested by measuring the performances of restructured codes. The suitability of the use of nonorthogonal coordinates for scattering purposes is tested by performing collinear calculations for the H+H-2 reaction.