速度计实时 时间依赖密度 功能紧固结合用于大型凝聚物质系统
Qiang Xu1, Mauro Del Ben2, Mahmut Sait Okyay1
1Materials Science & Engineering Program, Department of Chemistry, and Department of Physics & Astronomy, University of California-Riverside, Riverside, California 92521, United States.
Journal of chemical theory and computation
|November 13, 2023
概括
我们开发了一种新的计算方法,用于模拟大型材料中的电子动态. 这种方法可以实时分析成千上万个原子的复杂系统中的电子激发.
科学领域:
- 计算物理 计算物理
- 材料科学 材料科学 材料科学
- 量子化学 是一个量子化学.
背景情况:
- 在大型凝聚物质系统中精确模拟电子激发的计算要求很高.
- 现有的方法经常与现实世界材料的规模和复杂性作斗争.
研究的目的:
- 为实时电子动力学模拟引入一种新的,计算效率高的方法.
- 为了使电子激发在大型,周期性凝聚物质系统的研究.
主要方法:
- 实行速度计实时,时间依赖密度功能紧固结合 (VG-rtTDDFTB) 方法.
- 使用开源的DFTB+软件包进行模拟.
- 在各种大型材料系统上进行基准准确性和并行性.
主要成果:
- VG-rtTDDFTB方法证明了对数千个原子的系统有利的计算缩放.
- 成功模拟了激光诱导的电子动力学在一个512原子无形超级细胞.
- 在各种材料类型中验证精度和计算并行性.
结论:
- VG-rtTDDFTB方法显著提升了大型,复杂的凝聚物质系统的模拟能力.
- 这种方法为研究晶体缺陷,表面,纳米线和无形材料等系统中的电子动态开辟了新的途径.
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