Semiclassical initial value representation

A fully accurate description of chemical dynamics would be completely quantum mechanical. However, even with the best computers who have today, simulations of full quantum dynamics are restricted to a small number of atoms. On the other hand, simulations of classical dynamics routinely involves hundreds of thousands of atoms, or even more. Of course, pure classical dynamics does not include quantum effects.

The semiclassical initial value representation (SC-IVR) is an approach that uses many classical trajectories to approximate quantum dynamics. It has the accuracy to capture all quantum effects relevant to chemical dynamics, while being much easier to calculate than the full quantum dynamics. The research described below includes efforts to expand the SC-IVR and to make it more efficient.

Projects within this research line have included:

• Reducing the number of trajectories needed by using time-dependent sampling
• Reducing the per-trajectory cost with a new way to calculate the monodromy matrix

If you’re interested in getting more of an introduction to the SC-IVR, I’d recommend the first chapter of my dissertation.