TIFR
Department of Chemical Sciences
School of Natural Sciences

October 13, 2014 at 4.00 pm in AG-69

Title :

Accurate and Efficient Quantum Dynamics for Photo-Absorption and Molecule-Surface Scattering Processes

Abstract :

The major focus of the talk will be to explore the efficiency of parallelized TDDVR algorithm to perform dynamics on vibronically coupled electronic manifold for photo-absorption spectra [1] and molecule-surface scattering problem [2]. The parallelized algorithm shows closely linear scalability with increasing number of processors. The dynamical outcomes, e.g., population, photoelectron spectra and diffused interstellar bands etc. of this quantum-classical approach show good agreement with the findings of well established quantum dynamical MCTDH method [3]as well as experimental observations. We also carry out four (4D X 2D) and six (6D) dimensional quantum dynamics on an effective Hamiltonian derived by assuming weakly correlated interactions between molecular DOFs with surface modes and electron-hole pair (elhp) excitations through a Hartree product type wave function and depict the calculated sticking/transition probabilities as well as energy transfer from molecule to the surface at different surface temperature for D2(v=0, 1; j=0) - Cu(111) collision. The phonon modes change the chemisorption process, whereas both phonon and elhp interactions show physically meaningful trend both for sticking as well as transition probabilities w.r.t other theoretical calculations [4] and experimental results [5,6].


References:

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