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Related Experiment Video

Updated: Jun 18, 2026

Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior

Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior

Published on: April 13, 2016

Semiclassical nonlinear response functions for coupled anharmonic vibrations.

Scott M Gruenbaum¹, Roger F Loring

¹Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA.

The Journal of Chemical Physics

|December 2, 2009

Summary

This summary is machine-generated.

The Herman-Kluk approximation accurately models quantum coherence in spectroscopy. A new mean-trajectory method simplifies calculations for coupled anharmonic oscillators, preserving accuracy.

Related Experiment Videos

Last Updated: Jun 18, 2026

Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior

Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior

Published on: April 13, 2016

Area of Science:

Quantum dynamics
Spectroscopy
Computational chemistry

Background:

Vibrational response functions describe nuclear dynamics on a single electronic surface for spectroscopic observables.
The Herman-Kluk (HK) semiclassical approximation is known for accurately representing quantum coherence effects.

Purpose of the Study:

To demonstrate the accuracy of the Herman-Kluk (HK) semiclassical approximation for computing vibrational response functions.
To develop a more computationally efficient approximation that retains the accuracy of the HK method for quantum coherence effects.

Main Methods:

Utilized the Herman-Kluk (HK) semiclassical approximation to compute linear and nonlinear response functions for coupled anharmonic oscillators.
Developed a mean-trajectory (MT) approximation by analytically treating interference among classical trajectories in the HK method.
Propagated classical trajectories linked by transitions in action for the MT approximation.

Main Results:

The HK approximation accurately represents quantum coherence effects in response functions for coupled anharmonic oscillators.
The mean-trajectory (MT) approximation successfully reproduces these coherence effects.
The MT approximation offers a computationally tractable alternative to the HK method for systems with strong vibrational interactions.

Conclusions:

The Herman-Kluk approximation is a reliable tool for studying quantum coherence in spectroscopic observables.
The developed mean-trajectory approximation significantly reduces the computational cost while maintaining accuracy for complex vibrational dynamics.
This work provides a more efficient pathway for theoretical investigations of molecular vibrations and spectroscopic phenomena.