能量不是粒子数的凸函数,对于r-k粒子间电位,k>log34的粒子间电位
1Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada.
The Journal of chemical physics
|January 26, 2024
概括
具有特定排斥潜力的多粒子系统的能量不是凸起的,这导致了一些电子系统的负频段间隙. 这种由戴森轨道幅度表示的非凸度,对理论分析提出了挑战.
科学领域:
- 量子化学 是一个量子化学.
- 计算物理 计算物理
- 材料科学 材料科学 材料科学
背景情况:
- 关于粒子数的多粒子系统能量的凸度对于理解电子性质至关重要.
- 非凸度可以表现为负带间隙,其中电离潜力小于电子亲和力.
- 粒子间排斥潜力在确定能量凸度方面发挥着关键作用.
研究的目的:
- 为了研究多粒子系统的能量在粒子数方面非凸的条件.
- 探索非凸性对电子系统的影响,特别是关于带间隙.
- 识别非凸的能量行为的潜在特征.
主要方法:
- 对r-k粒子间排斥潜力的分析.
- 检查能量,粒子数和潜在参数之间的关系.
- 研究与电子附着相关的戴森轨道.
主要成果:
- 在k > log34 (约1.262) 时,对于r-k粒子间排斥潜力,多粒子系统的能量不是凸的.
- 具有这些潜力的有限电子系统可以表现出负带间隙 (化学硬度).
- 对于最低能量电子附着模式而言,戴森轨道的消失的小振幅是非凸性的明显标志.
结论:
- 对某些排斥潜力来说,能量的无凸性与粒子数有关.
- 负频段间隙是有限电子系统中这种非凸性的结果.
- 该研究强调了分析证明凸度的困难,并确定了非凸度行为的关键可观测指标.
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