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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
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Superadiabatic Forces via the Acceleration Gradient in Quantum Many-Body Dynamics
Moritz Brütting1, Thomas Trepl1, Daniel de Las Heras1
1Theoretische Physik II, Physikalisches Institut, Universitat Bayreuth, D-95440 Bayreuth, Germany.
Molecules (Basel, Switzerland)
|October 17, 2019
Summary
This study introduces a quantum power functional framework to model helium atom dynamics beyond the standard adiabatic approximation. The findings reveal the necessity of velocity and acceleration gradients for accurate interparticle interaction descriptions.
Area of Science:
- Quantum mechanics
- Computational chemistry
- Atomic physics
Background:
- The adiabatic approximation is a common simplification in quantum dynamics.
- Accurately describing interparticle interactions is crucial for atomic system simulations.
- The quantum power functional framework offers a formally exact approach.
Purpose of the Study:
- To apply the quantum power functional framework to a one-dimensional Hooke's helium model.
- To investigate dynamics beyond the density-based adiabatic approximation.
- To identify necessary components for describing interparticle effects.
Main Methods:
- Application of the quantum power functional framework.
- Analysis of one-body dynamics.
- Comparison with exact numerical solutions of the Schrödinger equation.
Main Results:
- Gradients of microscopic velocity and acceleration fields are essential for interparticle interactions.
- Analytical forms for superadiabatic force and transport contributions were proposed and validated.
- Superadiabatic contributions significantly impact dynamics and include effective dissipation.
Conclusions:
- The quantum power functional framework provides a more accurate description of atomic dynamics.
- Beyond the adiabatic approximation, superadiabatic effects are vital.
- This approach advances the simulation of quantum systems with electron correlation.
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