关于K的局部结构对称性的研究
Mega Novita1, Sigit Ristanto2, Ernawati Saptaningrum2
1Postgraduate Program of Science Education, Universitas PGRI Semarang, Semarang 50232, Indonesia.
Materials (Basel, Switzerland)
|June 10, 2023
概括
本研究探讨了局部结构对称如何影响Mn4+激活红色光的发光. 减少的Mn-F键长度和较低的对称性减少了电子对电子排斥,影响了发光特性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 发光的光度是非常的低.
背景情况:
- Mn4+活性化化物,特别是A2XF6:Mn4+和BXF6:Mn4+化合物,是众所周知的红色.
- 它们的发光性能严重依赖于围绕着剂离子的局部晶体结构.
- 之前的研究还没有研究局部结构对称对红色光发光的具体影响.
研究的目的:
- 调查局部结构对称化对K2XF6晶体中各种多类型的发光特性的影响,这些晶体被合Mn4+.
- 分析局部对称性和Mn-F键长度的变化如何影响能量水平和光学转换.
主要方法:
- 利用第一原则的方法,离散变量Xα (DV-Xα) 和离散变量多电子 (DVME),以建模七个原子集群.
- 计算了不同K2XF6晶体结构的分子轨道能量,多重能量水平和库伦积分.
- 集成的格子放松,配置依赖校正 (CDC) 和相关性校正 (CC) 以准确地复制多重能量.
主要成果:
- 观察到,减少Mn-F键长度会增加4A2g→4T2g (4F) 和4A2g→4T1g (4F) 的能量,同时减少2Eg→4A2g的能量.
- 发现较低的对称性导致较小的库伦积分数,减少电子对电子排斥.
- 质量复制的Mn4+化K2XF6晶体的多重能量.
结论:
- 局部结构对称性显著影响Mn4+化K2XF6红色光体的发光特性.
- 在较低对称性环境中减少电子对电子排斥是观察到R线能量变化的关键因素.
- 这项研究提供了通过结构控制来定制性能的基础见解.
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