调查面向外部电场对调节Fe中旋转转变温度的影响 (II) SCO复合体:理论视角
Rupesh Kumar Tiwari1, Rajdeep Paul1, Gopalan Rajaraman1
1Department of Chemistry, Indian Institute of Technology, Powai, Mumbai, India. rajaraman@chem.iitb.ac.in.
Dalton transactions (Cambridge, England : 2003)
|August 20, 2024
概括
研究人员使用面向外部电场 (OEEF) 来调整旋转交叉 (SCO) 综合体中的旋转过渡温度. 应用OEEF显著增加了过渡温度,为调整SCO材料特性提供了一种新方法.
科学领域:
- 材料科学:专注于自旋交叉 (SCO) 复合体及其电子性质.
- 计算化学:密度函数理论 (DFT) 用于分子性质预测的应用.
背景情况:
- 旋转交叉 (SCO) 复合体表现出两元稳定性,使其对各种应用具有吸引力.
- 一个关键的挑战是控制旋转过渡温度 (T1/2),通常需要复杂的合成或外部刺激,如光或压力.
- 现有的调整T1/2的方法对最终用户应用程序构成了整合挑战.
研究的目的:
- 为了研究使用面向外部电场 (OEEF) 作为刺激,以调节Fe(II) SCO复合体中的旋转过渡温度.
- 探索OEEF应用的可行性,作为调整SCO属性的新策略.
主要方法:
- 使用TPSSh函数的密度函数理论 (DFT) 计算对三个Fe(II) SCO复合体进行了计算:[Fe(phen) 2 ((NCS) 2),[Fe(bt) 2 ((NCS) 2],[Fe(py) 2 ((phen) 2 ((NCS) 2].
- 用定期和非定期计算来研究沿伪C2轴应用的OEEF的影响.
- 与五个额外的交换相关函数 (PBE,BLYP,B3LYP*,B3LYP,PBE0) 进行了基准测试.
主要成果:
- 发现OEEF的应用增加了Fe-ligand键的长度,并影响了旋转过渡.
- 在0.514V/Å的应用场中,高旋转 (HS) 状态成为所有三个复合体的基本状态.
- 增加OEEF强度显著增加了计算的旋转过渡温度 (T1/2),值从~111-160 K上升到~184-211 K.
- 对复合物1在Au(111) 上被吸附的计算表明,OEEF可以抵消由表面吸附引起的LS状态稳定.
结论:
- 定向外部电场 (OEEF) 提供了一种有效且迄今为止未知的策略,用于调整SCO综合体中的旋转过渡温度.
- 选择交换相关函数对于准确预测SCO行为至关重要,特别是在外部刺激下.
- OEEF应用程序提供了一个有前途的后制造方法,用于在表面支系统中实现所需的SCO特性.
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