晶体结构和Li2S-P2系统的相稳定性从第一原则开始
Ronald L Kam1,2, KyuJung Jun1,2, Luis Barroso-Luque1
1Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
Chemistry of materials : a publication of the American Chemical Society
|November 29, 2023
概括
本研究量化了Li2S-P2S5系统中超离子导体的热力学可访问性. 这些材料虽然变态稳定,但在热力学上是可访问的,振动和配置对于稳定性至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 计算材料科学科学 计算材料科学
背景情况:
- 2S-P2S5系统产生具有高室温离子导电性的超离子导体.
- 这些阶段的超稳定性需要理解它们的热力学可访问性.
研究的目的:
- 在Li2S-P2S5系统中计算确定晶相的热力学稳定性.
- 研究电子,配置和振动自由能量在相稳定中的作用.
- 为关键的超声波导体组合提出新的基态排序.
主要方法:
- 电子,配置和振动自由能量的第一原则计算.
- 为晶体Li2S-P2S5空间构建相位图.
- 分析 (振动和配置) 对相位稳定的贡献.
主要成果:
- 构建了Li2S-P2S5系统的相位图,预测了Li3PS4和Li7PS6多态和Li7P3S11.7的新基态排序.
- 重现了实验阶段稳定性趋势,包括多态过渡和高温不稳定性.
- 所有研究的超离子导体都被预测在环境温度下具有转移稳定性,但在热力学上是可访问的.
结论:
- 振动和配置对于准确描述超离子导体的稳定性至关重要.
- 在Li子格子中配置障碍对于预测配置来说至关重要.
- 快速的离子扩散和热力学稳定性之间存在强烈的相关性,由配置驱动.
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