Papers by HERNAN DARIO HUERTAS ESTRADA
Physical Review A, 1989
The time-dependent description of the dynamics of electron-molecule collision complexes is out- l... more The time-dependent description of the dynamics of electron-molecule collision complexes is out- lined within the framework of Feshbach's projection-operator formalism. It is shown that the equation of motion for the quantum-mechanical wave packet representing the collision complex contains effective-potential terms which are nonlocal as well as non-Markovian, that is, the time develop- rnent depends on the previous history of the system. The space-time integro-differential equation of motion is explicitly (numerically) solved for a class of simple models using expansions into complete sets of functions in both space and time. The exact wave-packet dynamics is compared with the re- sults obtained in the local-complex-potential approximation, which corresponds to the Markovian approximation for the decay dynamics. The concepts and numerical methods are illustrated for a model of the well-known 'll, , shape resonance in electron-N, scattering, where the boomerang effect is reproduced. For a model of a p-wave shape resonance near threshold, novel qualitative effects are revealed, namely, nonmonotonic electronic decay (recapture of electrorls from the continuum) as well as strong frictional effects i» the vibrational motion. The time-dependent description of virtual-state threshold effects in s-wave scattering is also briefly considered.
Uploads
Papers by HERNAN DARIO HUERTAS ESTRADA