金属固体的高度精确的电子结构来自配对集群理论与非扰动的三次激发
Verena A Neufeld1,2, Timothy C Berkelbach1
11Department of Chemistry, Columbia University, New York, New York 10027, USA.
Physical review letters
|November 17, 2023
概括
用单,双和扰动三次激发 (CCSD(T)) 结合集群理论对于金属是有限的. 新的方法,合集群三次激发 (CCSDT) 和环-CCSDT,准确地模拟金属系统并提高计算化学的准确性.
科学领域:
- 量子化学是一种量子化学.
- 材料科学 是一种材料科学.
- 计算物理学的计算物理.
背景情况:
- 配对集群理论与单,双和扰动三次激发 (CCSD(T)) 是量子化学准确性的基准.
- 由于红外分歧,CCSD ((T) 不适用于3D金属,限制了其在材料科学中的使用.
- 准确的金属系统建模对于理解它们的特性至关重要.
研究的目的:
- 扩展结合集群理论,以准确描述金属系统.
- 开发和应用包括完全,非扰动性包含三重激发的方法.
- 研究三次激发对均电子气体的相关能量和固体的结构性质的影响.
主要方法:
- 三重激发的完全,非扰动性包含 (CCSDT).
- 开发一种新的代方法,环-合-集群三次激发 (环-CCSDT),使用N^7缩放.
- 将CCSDT和环CCSDT应用于统一的电子气体和固体.
- 半实证合集群方法的研究.
主要成果:
- 包含连接的三次激发对于金属系统的高精度至关重要.
- 均的电子气体和固体使用CCSDT和环-CCSDT准确地建模.
- 环CCSDT实现了与CCSDT相同的计算缩放,同时包括必要的三重激发.
- 基于自旋组件缩放和可区分集群近似的半经验方法提高了准确性.
结论:
- 开发的CCSDT和环CCSDT方法克服了金属系统中CCSDT的局限性.
- 精确的金属特性建模是可以实现的,包括三次激发.
- 结合集群方法的进一步开发对材料科学应用有希望.
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