Merging Coherent States with Density Functional Theory for Enhanced Chemical Dynamics Simulation
This project explores a novel integration of coherent states (CS) theory with density functional theory (DFT) to simulate chemical reactions more effectively. CS offers a classical-like framework for quantum dynamics, allowing for an over-complete representation of wave functions. By employing narrow, frozen Gaussian wave packets to describe nuclei and a single-determinantal Thouless CS for electrons, the methodology enhances electron correlation effects at a lower computational cost. Implemented in the CSTechG program, this approach offers improvements over the Car-Parrinello method with a non-redundant electronic representation.
Merging Coherent States with Density Functional Theory for Enhanced Chemical Dynamics Simulation
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Presentation Transcript
Combined Coherent-States/Density-Functional-Theory DynamicsACS PRF# 45420-AC6Jorge A. MoralesDepartment of Chemistry and Biochemistry Texas Tech University PO Box 41061, Lubbock, TX 79409-1061, USA The vast realm of the coherent states (CS) theory can provide a convenient framework for the direct simulation of chemical reactions. Specifically, CS sets furnish adequate over-complete sets to represent wave functions and to express the quantum dynamical equations of a molecular system in a classical-like format. In this project, we are merging such a CS approach to chemical dynamics with density functional theory capabilities to benefit from their adequate description of electron correlation effects at low computational cost. In the resulting methodology, nuclei are described by a product of narrow, frozen Gaussian wave packets, which is separable into translational, rotational, and vibrational quasi-classical CS, whereas electrons are described by a single-determinantal Thouless CS in a Kohn-Sham fashion. This approach improves some features of the celebrated Car-Parrinello method by providing: an ab initio CS Lagrangian, a quasi-classical CS analysis of dynamical properties at final time, and a non-redundant representation of an electronic single-determinantal state. This methodology is being implemented into the CSTechG program package. Figure: Four snapshots of the time-dependent charge density in H+ + C2H2 at ELab = 30 eV