Conditional Born-Oppenheimer Dynamics: Quantum Dynamics Simulations for the Model Porphine
Conditional Born-Oppenheimer Dynamics: Quantum Dynamics Simulations for the Model Porphine
G. Albareda, J. M. Bofill, I. Tavernelli, F. Huarte-Larrañaga, F. Illas, A. Rubio. J. Chem. Phys. Lett., 6 (2015) 1529.
Schematic representation of the conditional wave function concept for the model Porphine.
We report a new theoretical approach to solve adiabatic quantum molecular dynamics halfway between wave function and trajectory-based methods. The evolution of a N-body nuclear wave function moving on a 3N-dimensional Bornppenheimer potential-energy hyper-surface is rewritten in terms of single-nuclei wave functions evolving nonunitarily on a 3-dimensional potential-energy surface that depends parametrically on the configuration of an ensemble of generally defined trajectories. The scheme is exact and, together with the use of trajectory-based statistical techniques, can be exploited to circumvent the calculation and storage of many-body quantities (e.g., wave function and potential-energy surface) whose size scales exponentially with the number of nuclear degrees of freedom. As a proof of concept, we present numerical simulations of a 2-dimensional model porphine where switching from concerted to sequential double proton transfer (and back) is induced quantum mechanically.