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Related Experiment Video

Updated: Jan 6, 2026

Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics

Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics

Published on: April 12, 2019

Dissipative quantum dynamics using the stochastic surrogate Hamiltonian approach.

F Habecker¹, R Röhse¹, T Klüner¹

¹Theoretical Chemistry, Department of Chemistry, Carl von Ossietzky University of Oldenburg, Ammerländer Heerstr. 114-118, Oldenburg D-26129, Germany.

The Journal of Chemical Physics

|October 10, 2019

Summary

We developed a new algorithm for simulating open quantum systems, enhancing the Stochastic Surrogate Hamiltonian approach. This method accurately models nuclear relaxation and electronic excitation in processes like photodesorption.

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Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics

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Area of Science:

Quantum Dynamics
Computational Chemistry
Surface Science

Background:

The Stochastic Surrogate Hamiltonian (SSH) approach simulates open quantum system dynamics.
Existing methods require refinement for complex molecular processes.

Purpose of the Study:

To present a modified SSH algorithm for improved simulation of quantum dynamics.
To apply the modified SSH approach to ab initio calculations of photodesorption.

Main Methods:

Modified Stochastic Surrogate Hamiltonian algorithm for swap procedures.
Testing with harmonic and Morse oscillator models for nuclear relaxation.
Application to simulate electronic excitation and relaxation in photodesorption.

Main Results:

The modified SSH algorithm successfully simulated nuclear relaxation dynamics.
The first ab initio application of SSH to simulate electronic excitation and relaxation in photodesorption was achieved.
Results for laser-induced NO desorption from NiO(100) were obtained and compared to a benchmark.

Conclusions:

The modified SSH approach provides a robust method for simulating open quantum system dynamics, including complex photodesorption processes.
This work demonstrates the utility of SSH in ab initio computational chemistry and surface science.
The developed algorithm offers a valuable tool for understanding quantum phenomena in molecular systems.