Antisymmertrized Molecular Dynamics

Jincheng Zhang

Quantum information has revolutionized various fields, and molecular dynamics (MD) simulations, while powerful, often struggle to capture the subtle complexities of molecular behavior. This paper introduces a novel computational framework, Quantum Information in Molecular Dynamics Calculation, leveraging quantum information and geometric constraints to provide a deeper understanding of molecular stability. We propose a new method for modeling molecular structure evolution, guided by the principles of quantum entanglement and geometric limitations, offering a significant advancement over traditional MD approaches. This framework aims to unveil the underlying geometric factors influencing molecular stability, ultimately providing insights into the fundamental principles governing molecular interactions.

Søren Toxværd

Jincheng Zhang

Molecular dynamics (MD) simulations are instrumental in studying the behavior of complex molecules and materials, but their computational cost can be prohibitive for simulating large systems. This paper introduces a novel algorithm for non-linear wave function collapse (NWWC) in molecular dynamics simulations, designed to enhance the accuracy and speed of simulations of complex molecules. The core mechanism centers around a dynamically adjusting collapse rate, guided by observed molecular motion, effectively mitigating the effects of thermal noise and leading to improved simulation results. The algorithm addresses the limitations of traditional MD methods by providing a more robust and efficient approach to exploring molecular systems. This work explores the potential of adapting the collapse rate to the dynamics of the system, resulting in more accurate and faster simulations of complex molecules.

Benedikt M. Reible, Somayeh Ahmadkhani, Luigi Delle Site

The Lindblad equation determines the time evolution of the density operator of open quantum systems. While valid for any system size, its use is, in practice, restricted to prototype/surrogate models with the aim of tackling specific aspects of the overall quantum complexity of a multi-atomic system. Path integral molecular dynamics (PIMD) instead provides static and dynamical quantum statistical averages of physical observables for systems in equilibrium composed of up to thousands of atoms over timescales up to nanoseconds, under the condition that short-time quantum coherence is not relevant for the properties of interest. PIMD relies on the well-established technique of molecular dynamics (MD) with its associated classical trajectories. However, it cannot describe a direct time evolution of a system and its convergence to a stationary state in situations out of equilibrium. In this work, we analyze the link between the Lindblad equation and PIMD; specifically, we will discuss how PIMD can actually be used to calculate the time evolution of ensemble-averaged physical observables and their convergence to a stationary state for situations out of equilibrium, bypassing the need of explicitly solving the Lindblad equation. Yet, at the same time, the Lindblad equation and PIMD are linked to one another through a formal relation of equivalence, which provides an argument for the consistency of PIMD results, namely the positivity of the density operator at any time. A numerical study of a prototype system, which is of interest in chemical physics, will be used to showcase the method.

Hisashi Horiuchi, Akira Ono