X-ray diffraction, Raman spectroscopic, and solid-state NMR studies of the group 14 metal-(tetracarbonyl)cobalt complexes Ph3MCo(CO)4 (M = Si, Sn, Pb)
X-ray diffraction, Raman spectroscopic, and solid-state NMR studies of the group 14 metal-(tetracarbonyl)cobalt complexes Ph3MCo(CO)4 (M = Si, Sn, Pb)
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第 14 族金属-（四羰基）钴配合物 Ph3MCo(CO)4（M = Si、Sn、Pb）的 X 射线衍射、拉曼光谱和固态 NMR 研究
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
F. Bélanger
中科院分区：
文献类型：
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作者：
J. Geller;J. Wosnick;I. Butler;D. Gilson;F. Morin;F. Bélanger
单晶X-射线衍射研究表明，三个标题化合物是类质同象的，属于三斜晶系空间群P，具有轻微扭曲的三角双锥几何结构的钴。给出了固体29 Si、119 Sn和207 Pb交叉极化魔角自旋（CP MAS）NMR谱。提取了间接自旋自旋耦合常数（J）、四极偶极位移（d）、直接偶极耦合常数（D'）、自旋自旋耦合各向异性（ΔJ）和化学位移张量。约化耦合常数与原子核处s电子密度的关系图表明，费米接触项可能是锡和铅络合物的主导项;然而，所有络合物的大ΔJ表明也存在显著的各向异性项。关键词：29Si，119Sn，207Pb CP MAS NMR，tetracarbonyl cobalt，spin-spin coupling，chemical shift tensor，quadrupole coupling，Fermi contact，cobalt group 14.
Single-crystal X-ray diffraction studies illustrate that the three title compounds are isomorphous, belonging to the triclinic space group P, with slightly distorted trigonal bipyramidal geometry about cobalt. The solid-state 29Si, 119Sn, and 207Pb cross-polarization magic angle spinning (CP MAS) NMR spectra are presented. The indirect spinspin coupling constant (J), quadrupolardipolar shift (d), direct dipolar coupling constant (D' ), anisotropy in spinspin coupling (ΔJ), and the chemical shift tensor were extracted. A plot of the reduced coupling constant vs. s-electron densities at the nucleus indicates that the Fermi contact term may be dominant for the tin and lead complexes; however, the large ΔJ for all complexes indicate that there are also significant anisotropic terms. Trends in the Raman scattering spectra are also discussed.Key words: 29Si, 119Sn, and 207Pb CP MAS NMR, tetracarbonyl cobalt, spinspin coupling, chemical shift tensor, quadrupole coupling, Fermi contact, cobaltgroup 14.