在热电学中探索结合立体化学活性单对和动效应,并利用机器学习潜力
Harpriya Minhas1, Rahul Kumar Sharma1, Biswarup Pathak1
1Department of Chemistry, Indian Institute of Technology (IIT) Indore, Indore, Madhya Pradesh 453552, India.
The journal of physical chemistry letters
|May 13, 2025
概括
立体化学活性单一对 (SCALP) 和动原子显著影响热电材料. 机器学习潜力在AAsSe2中揭示了它们的综合效应,通过增强的声子散射来降低热导率.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 计算化学计算化学
背景情况:
- 立体化学活性单一对 (SCALP) 破坏对称性并影响热电性质.
- 的原子扰乱了声子传输,影响了导热性.
- 在非中心对称结构中用SCALP和动的原子计算热传输对初始方法来说具有挑战性.
研究的目的:
- 为了研究SCALP和动原子对AAsSe2 (A = Li或Na) 中的热电性质的联合作用.
- 利用机器学习的原子间潜力 (MLIP) 来探索这些复杂的相互作用.
- 了解这些材料中无声和声子散射的潜在机制.
主要方法:
- 使用机器学习的原子间潜力 (MLIP) 进行模拟.
- 分析AAsSe2系统的结构和振动特性.
- 调查SCALP (特别是As 4s^2) 和动原子在诱导无和性的作用.
主要成果:
- 在γ-NaAsSe2中鉴定出强烈的无声性,原因是声模式和As 4s^2SCALP诱导的静电相互作用.
- 观察到减少了单对角和独特的化学键,涉及抗键状态.
- 证明了声原子振动,声软化,结构扭曲和增强的声散射有助于高无和性.
结论:
- 在AAsSe2材料中,SCALP和动原子协同增强无声和声子散射.
- MLIP是研究复杂热电材料的有效工具.
- 这项研究通过了解这些组合效应,加速了先进热电材料的设计.
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