First-principles semiclassical initial value representation molecular dynamics.

Multiple coherent states for first-principles semiclassical initial value representation molecular dynamics.

A multiple coherent states implementation of the semiclassical approximation is introduced and employed to obtain the power spectra with a few classical trajectories. The method is integrated with the time-averaging semiclassical initial value representation to successfully reproduce anharmonicity and Fermi resonance splittings at a level of accuracy comparable to semiclassical simulations of t...

Determination of molecular vibrational state energies using the ab initio semiclassical initial value representation: application to formaldehyde.

We have demonstrated the use of ab initio molecular dynamics (AIMD) trajectories to compute the vibrational energy levels of molecular systems in the context of the semiclassical initial value representation (SC-IVR). A relatively low level of electronic structure theory (HF/3-21G) was used in this proof-of-principle study. Formaldehyde was used as a test case for the determination of accurate ...

First - Principles Semiclassical Initial Value Representation

First principles semiclassical calculations of vibrational eigenfunctions.

Vibrational eigenfunctions are calculated on-the-fly using semiclassical methods in conjunction with ab initio density functional theory classical trajectories. Various semiclassical approximations based on the time-dependent representation of the eigenfunctions are tested on an analytical potential describing the chemisorption of CO on Cu(100). Then, first principles semiclassical vibrational ...

Semiclassical initial value representation for electronically nonadiabatic molecular dynamics

The semiclassical initial value representation ~SC-IVR!, which has recently seen a great deal of interest for treating nuclear dynamics on a single potential energy surface, is generalized to be able to describe electronically nonadiabatic ~i.e., multisurface! processes. The essential idea is a quantization of the classical electron-nuclear Hamiltonian of Meyer and Miller @J. Chem. Phys. 70, 32...