Reactive Scattering and Quantum Dynamics

Reactive scattering and quantum dynamics (RSQD) methods are important to both scientific and technological development endeavors. Because the behavior of chemical species (molecule—molecule, atom-molecule, electron scattering, etc.) is rigorously described by quantum mechanics, which is built into the RSQD theoretical methods, accurate and converged solutions are achievable. Pursuant to a central goal of theoretical chemistry, these methods determine the cross sections and rates of chemical reactions. There are three basic methods  

Time-dependent wave packets (interpretation of scattering results) 

As noted, there are relatively few groups working directly on implementations of RSQD methodologies for MPP computer systems. We now consider 

Chasman and co-workers derived the time complexity of each combination of Hamiltonian evaluation and time integration method for both serial and parallel computers. Table 1 shows their results for systems of two and three dimensions. This time complexity can be used to develop a computational cost model of their application. A full analysis of the communication properties of their application could be developed to derive a complete performance model. This, in turn, could be used to determine the time to completion for a given problem on a given computer or, alternatively, the performance of a given problem on a new parallel supercomputer. 

total number of processors Nq, number of terms in Chebyshev expansion. 

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