Zero-Point Energy Leakage in Quantum Thermal Bath Molecular Dynamics Simulations

Abstract

The quantum thermal bath (QTB) has been presented as analternative to path-integral-based methods to introduce nuclear quantumeffects in molecular dynamics simulations. The method has proved to beefficient, yielding accurate results for various systems. However, the QTBmethod is prone to zero-point energy leakage (ZPEL) in highly anharmonicsystems. This is a well-known problem in methods based on classicaltrajectories where part of the energy of the high-frequency modes istransferred to the low-frequency modes leading to a wrong energydistribution. In some cases, the ZPEL can have dramatic consequences onthe properties of the system. Thus, we investigate the ZPEL by testing theQTB method on selected systems with increasing complexity in order to studythe conditions and the parameters that influence the leakage. We also analyze the consequences of the ZPEL on the structuraland vibrational properties of the system. We find that the leakage is particularly dependent on the damping coefficient and thatincreasing its value can reduce and, in some cases, completely remove the ZPEL. When using sufficiently high values for thedamping coefficient, the expected energy distribution among the vibrational modes is ensured. In this case, the QTB methodgives very encouraging results. In particular, the structural properties are well-reproduced. The dynamical properties should beregarded with caution although valuable information can still be extracted from the vibrational spectrum, even for large values ofthe damping term.

References in corpus (10)

• First-principles theory of ferroelectric phase transitions for perovskites: The case of BaTiO3
• Nuclear quantum effects in solids using a colored-noise thermostat
• Effect of quantum fluctuations on structural phase transitions in SrTiO_3 and BaTiO_3
• Colored-noise thermostats à la carte
• Langevin Dynamics in Constant Pressure Extended Systems
• Comparison of Dissipative Particle Dynamics and Langevin thermostats for out-of-equilibrium simulations of polymeric systems
• Portable implementation of a quantum thermal bath for molecular dynamics simulations
• Semi-quantum approach to molecular dynamics simulation of thermal properties of low-dimensional nanostructures
• Simulation of quantum zero-point effects in water using a frequency-dependent thermostat
• Low-temperature anharmonicity of barium titanate: a path-integral molecular dynamics study

Cited by in corpus (14)

• Where does the energy go during the interstellar NH${}_3$ formation on water ice? A computational study
• Ehrenfest+R Dynamics I: A Mixed Quantum-Classical Electrodynamics Simulation of Spontaneous Emission
• Converged Colored Noise Path Integral Molecular Dynamics Study of the Zundel Cation down to Ultra-low Temperatures at Coupled Cluster Accuracy
• Herman-Kluk propagator is free from zero-point energy leakage
• Deciphering the Influence of Ground-State Distributions on the Calculation of Photolysis Observables
• Nuclear Quantum Effects in liquid water at near classical computational cost using the adaptive Quantum Thermal Bath
• Routine Molecular Dynamics Simulations Including Nuclear Quantum Effects: from Force Fields to Machine Learning Potentials
• Generalized Discrete Truncated Wigner Approximation for Nonadiabtic Quantum-Classical Dynamics
• Mixed Quantum/Classical Theory for Rotational Energy Exchange in Symmetric-Top-Rotor + Linear-Rotor Collisions and a Case Study of $\mathrm{N}{\mathrm{D}}_3+{\mathrm{D}}_2$ System
• Non-Linear Correlation Functions and Zero-Point Energy Flow in Mixed Quantum-Classical Semiclassical Dynamics
• Nuclear quantum effects in molecular dynamics simulations
• First-principles study of phase transition in cadmium titanate by molecular dynamics incorporating nuclear quantum effects
• Spontaneous damage annealing reactions as a possible source of low energy excess in semiconductor detectors
• Nuclear Quantum Effects in Multi-Step Condensed Matter Chemistry: A Path Integral Molecular Dynamics Study of Thermal Decomposition