A simple quantum-defect model gives analytic expressions for the complex scattering length and threshold collision rates of ultracold molecules. If the probability of reaction in the short-range part of the collision is high, the model gives universal rate constants for s- and p-wave collisions that are independent of short-range dynamics. This model explains the magnitudes of the recently meas...

Data on the decomposition of 1,3-butadiene have been analyzed. The numerous isomerization processes that have recently been proposed as additional channels for decomposition have been considered. Energy transfer effects have been taken into account through the solution of the time-dependent master equation. We confirm recent supposition that direct formation of ethylene and acetylene is a major...

We present a new approach for the direct ~and correct! calculation of thermal rate constants k(T) ~‘‘direct’’ meaning that one avoids having to solve the state-to-state reactive scattering problem, and ‘‘correct’’ meaning that the method contains no inherent approximations!. The rate constant is obtained from the long time limit of the flux-position correlation function, Cf ,s(t), whose calcula...

The kinetics of biomolecular systems can be quantified by calculating the stochastic rate constants that govern the biomolecular state vs time trajectories (i.e., state trajectories) of individual biomolecules. To do so, the experimental signal vs time trajectories (i.e., signal trajectories) obtained from observing individual biomolecules are often idealized to generate state trajectories by m...

Langevin described a model for the interaction between an ion and a neutral nearly a century ago and since then, many modifications have been introduced to adjust for specific circumstances. This work discusses the induced dipole–induced dipole interaction between an ion and a neutral without a permanent dipole and introduces an anisotropic adjustment. A point polarizable ion model (PPI) and an...