单晶X射线衍射研究三种Yb@C82异构体与Ni ((II) ((octaethylporphyrin) 同结晶
Mitsuaki Suzuki1, Zdenek Slanina, Naomi Mizorogi
1Life Science Center of Tsukuba Advanced Research Alliance, University of Tsukuba, Ibaraki, Japan.
Journal of the American Chemical Society
|October 23, 2012
概括
这项研究使用X射线晶体学精确地绘制了三种Yb@C(82) 异构体的结构. 离子 (Yb2+) 显示在富勒烯内的首选位置,由理论计算证实.
科学领域:
- 富勒和金属富勒
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 金属烯,如Yb@C(82),由于其独特的电子和结构性质,具有显著的兴趣.
- 了解金属离子在富勒烯中的确切位置对于预测它们的行为和应用至关重要.
- 之前对Yb@C(82) 异构体的结构研究是有限的,特别是对于封装双价金属离子的异构体.
研究的目的:
- 准确阐明三个特定的Yb@C(82) 同体 (Yb@C(2) ((5) -C(82),Yb@C(s) ((6) -C(82和Yb@C(2v) ((9) -C(82)) 的分子结构.
- 为了确定这些富勒烯内的Yb(2+) 离子的首选位置.
- 提供第一个关于金属富勒烯的晶体学报告,其中C{2v) }{9}-C{82) 囊封装了双价金属离子.
主要方法:
- Yb@C(82) 同位体与Ni(II) ((八甲基氨酸) 的联合结晶.
- 使用X射线衍射进行精确的结晶学阐明.
- 使用B3LYP理论水平分析静电电位图的理论计算.
主要成果:
- 在所有研究的Yb@C(82) 异构体中确定了多个金属位置.
- 在Yb@C(2) ((5) -C(82) 和Yb@C(2v) ((9) -C(82) 异构体中,Yb(2+) 离子主要定位在六角环附近.
- 在Yb@C ((s) ((6) -C ((82)) 同位体中,Yb ((2+) 离子在[5,6,6]连接的碳原子附近被发现.
- 理论计算证实了这些金属位置与能量最小值和稳定配置相对应.
结论:
- 该研究提供了三种Yb@C(82) 异构体的精确结构数据,详细说明了子对称性和金属离子位置.
- 这些发现揭示了Yb2+) 离子在不同的C82结构中的特定偏好的结合点.
- 这项工作在金属烯的结构性表征方面取得了重大进展,特别是M(2+)@[C(2v)(9) -C(82)](2-) 系统.
相关概念视频
02:34Structural Isomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
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02:18X-ray Crystallography
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Diffraction
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01:29Determination of Crystal Structures
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02:58Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
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CFT focuses on...
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Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
02:52Stereoisomerism
Isomerism in Complexes
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Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...