谱分区的科恩-沙姆密度函数理论.
Babak Sadigh1, Daniel Åberg1, John Pask1
1Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
Physical review. E
|November 18, 2023
概括
我们开发了一个新的变化方案,通过分割密度矩阵来近似Kohn-Sham能量函数. 这种方法提高了热密物质计算的计算效率,特别是在高温下.
科学领域:
- 计算物理 计算物理
- 量子化学 是一个量子化学.
- 材料科学 材料科学 材料科学
背景情况:
- 科恩-沙姆密度函数理论 (DFT) 是电子结构计算的基石.
- 接近Kohn-Sham自由能量函数仍然是一个计算挑战,特别是在复杂的系统.
- 现有的方法可能会与表现出跨能量尺度的多样化电子行为系统作斗争.
研究的目的:
- 引入一个一般的,可变的方案,以接近Kohn-Sham的自由能源函数.
- 开发一种系统地将密度矩阵分成光谱域的方法.
- 为了使像热密物质这样的系统能够进行更有效,更准确的计算.
主要方法:
- 提出了一个变化方案,将密度矩阵分成独立的光谱域.
- 使用了对自由能量的通用化热贡献,允许独立表示.
- 设计了一种数值程序,用于计算与光谱分区相关的通用.
主要成果:
- 拟议的方案为准确的Kohn-Sham免费能源提供了上限.
- 应用于热和热密的物质,它显著降低了在高温下计算成本.
- 该方法解决了在高温下标准投影机增强波 (PAW) 方法完整性的局限性.
结论:
- 频谱分区为具有多能模式占用子空间的系统的Kohn-Sham计算提供了一个强大的框架.
- 该方法在温密物质模拟中显示了大量的计算节约.
- 这种方法为在高温下进行电子结构计算的挑战提供了系统的解决方案.
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