在一个生物启发的N3S2合体场中,Ni (II) 的固态旋转交叉
Huaibo Ma1, Jeffrey L Petersen, Victor G Young
1Department of Chemistry and Biochemistry, Ohio University, Athens, Ohio 45701, United States.
Journal of the American Chemical Society
|March 29, 2011
概括
这项研究揭示了复合体中的旋转交叉与生物启发的配体集. 一个分子在冷却时从高旋转转向二磁性状态的旋转过渡.
科学领域:
- 无机化学 无机化学 有机化学
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
背景情况:
- 复合物与N(3) S(2) 连接体集具有兴趣,因为它们的生物灵感性质.
- 金属复合体中的旋转交叉现象可能导致磁性和结构性质的变化.
研究的目的:
- 为了研究一种新的 (II) 复合体Tp,Ph,Me,NiS,2CNMe,2的旋转交叉行为.
- 用温度依赖的技术来描述与旋转交叉相关的结构和磁性变化.
主要方法:
- 温度依赖的X射线晶体学以观察结构变化.
- 测量磁感应度以确定旋转状态.
- 将易感性数据与旋转平衡模型相匹配.
主要成果:
- 复合体呈现出一个五坐标的,正方形的金字塔形几何.
- 在293K时,两个独立的分子 (Ni1和Ni2) 都具有高旋转 (S=1) Ni(II).
- 在冷却到123K时,Ni2分子经历了旋转交叉到二磁性 (S=0) 状态,显示出明显的结构变化,而Ni1则保持高旋转,直到100K以下.
结论:
- 该综合体展示了温度诱导的自旋交叉,两个结晶学上独立的分子之间的差异性行为.
- 在Ni2的自旋平衡是由热力学参数 (ΔH°和ΔS°) 的特征,表明与格子效应的合较弱.
- 这项研究突显了自旋交叉在具有量身定制的连接体环境的复合体中的可调性.
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