Elinvar effect in $β-$Ti simulated by on-the-fly trained moment tensor potential

Phase transitions of hybrid perovskites simulated by machine-learning force fields trained on-the-fly with Bayesian inference

Realistic finite temperature simulations of matter are a formidable challenge for first principles methods. Long simulation times and large length scales are required, demanding years of compute time. Here we present an on-the-fly machine learning scheme that generates force fields automatically during molecular dynamics simulations. This opens up the required time and length scales, while retaining the distinctive chemical precision of first principles methods and minimizing the need for human intervention. The method is widely applicable to multi-element complex systems. We demonstrate its p…

$α$-$β$ phase transition of zirconium predicted by on-the-fly machine-learned force field

The accurate prediction of solid-solid structural phase transitions at finite temperature is a challenging task, since the dynamics is so slow that direct simulations of the phase transitions by first-principles (FP) methods are typically not possible. Here, we study the $α$-$β$ phase transition of Zr at ambient pressure by means of on-the-fly machine-learned force fields. These are automatically generated during FP molecular dynamics (MD) simulations without the need of human intervention, while retaining almost FP accuracy. Our MD simulations successfully reproduce the first-order displacive…

StructOpt: A modular materials structure optimization suite incorporating experimental data and simulated energies

StructOpt, an open-source structure optimization suite, applies genetic algorithm and particle swarm methods to obtain atomic structures that minimize an objective function. The objective function typically consists of the energy and the error between simulated and experimental data, which is typically applied to determine structures that minimize energy to the extent possible while also being fully consistent with available experimental data. We present example use cases including the structure of a metastable Pt nanoparticle determined from energetic and scanning transmission electron micros…

高保真模拟飞冲击发能量晶体-粘结剂系统的冲击起爆

High-fidelity simulations of shock initiation of an energetic crystal-binder system due to flyer impact

本文通过高保真meso尺度计算框架研究飞冲击发能量晶体-粘结剂系统，采用高阶WENO方案和物理准确的材料相互作用模型，评估数值处理和材料建模对meso尺度模拟的影响。