Time-dependent quantum mechanical wave packet dynamics

Abstract

Starting from a model study of collinear (H, H2) exchange reaction in 1959, the time-dependent quantum mechanical wave packet (TDQMWP) method has come a long way in dealing with systems...

Structure and dynamics of electronically excited molecular systems

“…Although the above method yields precise location of the vibronic eigenvalues, the eigenvalue problem (Equation ( 30)) becomes computationally demanding and often intractable for systems of growing size in terms of electronic and nuclear DOF. The traditional wave packet (WP) propagation methods 31 on a grid are also not viable to treat multimode and multistate quantum dynamics for large systems.…”

“…In order to facilitate comparison with experiment, the vibronic eigenvalue spectrum calculated with the prescription demonstrated above is convoluted with a line shape function to generate a spectral envelope For example, the can be taken as a Lorentzian function with full width at the half maximum (FWHM) Although the above method yields precise location of the vibronic eigenvalues, the eigenvalue problem (Equation ()) becomes computationally demanding and often intractable for systems of growing size in terms of electronic and nuclear DOF. The traditional wave packet (WP) propagation methods 31 on a grid are also not viable to treat multimode and multistate quantum dynamics for large systems.…”

“…A number of approaches have been developed over the past decades to treat nuclear dynamics on the coupled multisheeted electronic states. While for systems with fewer nuclear and electronic degrees of freedom (DOF) traditional time-dependent or time-independent quantum mechanical methods are computationally affordable, 31 they become prohibitively difficult to implement with increasing number of DOF for large systems. Introduction of the idea of Gaussian wave packets by Heller 32,33 led to a significant advancement in the field and methods both of approximate and exact categories were developed to treat nonadiabatic dynamics.…”

Electronic nonadiabatic effects in the state-to-state dynamics of the H + H2 → H2 + H exchange reaction with a vibrationally excited reagent

“…37–39,41,42,47 However, the role of the upper adiabatic PES on the reaction dynamics of the lower adiabatic PES was difficult to ascertain and remains a challenge for further studies on this seemingly simple reaction. 51…”

“…[37][38][39]41,42,47 However, the role of the upper adiabatic PES on the reaction dynamics of the lower adiabatic PES was difficult to ascertain and remains a challenge for further studies on this seemingly simple reaction. 51 Among many interesting dynamical features embedded in this reactive system, the most intriguing one is the GP effect, which has puzzled both theorists and experimentalists over a long period of time. 52 The GP effect on the dynamics of this reaction was controversial for some time in the past [34][35][36][53][54][55] and since then great efforts have been made both experimentally 13,[56][57][58][59][60][61] and theoretically 27,[35][36][37][38][39][40][41]55 to search for any signature of this effect.…”