Methods for the treatment of multiple states in non-adiabatic direct quantum dynamics simulations

[摘要] Following the pioneering work of Zewail, the field of Femtochemistry was opened up to experimental studies. However, the interpretation of the results of these studies is often difficult and hence theoretical and computational methods for the modelling of these processes have been developed. In these dynamical systems highly quantum behaviours are exhibited and hence the MCTDH method was developed as a grid-based full solution to the Time-Dependent Schrödinger equation. The vMCG method, an alternative formulation to MCTDH, has recently been extended to the Direct-Dynamics-vMCG (DD-vMCG) method. Here, Gaussian basis-functions are propagated on surfaces which are calculated “on-the-fly”. In this study two highly relevant systems have been used, formamide and 2-pyridone, to test the limitations of the DD-vMCG method combining high-level quantum chemistry calculations with a large number of excited states, and a challenging number of degrees of freedom.The recently developed attosecond laser spectroscopy utilises ultra-fast laser pulses in order to study the dynamics of electrons. Accordingly, computational methods are required for the interpretation of these results. In this thesis the initial testing, development and implementation of a new Ehrenfest-MCG method is presented, with test dynamics run on a highly conjugated molecule, allene, a system where electron dynamics is key.

[发布机构] University:University of Birmingham;Department:School of Chemistry

[关键词] Q Science;QD Chemistry