A Multitechnique Approach to Spin-Flips for Cp2Cr(II) Chemistry in Confined State
A Multitechnique Approach to Spin-Flips for Cp2Cr(II) Chemistry in Confined State
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DOI：
10.1021/jp907986w
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发表时间：
2010-02
影响因子：
3.7
通讯作者：
Jane Estephane;E. Groppo;J. Vitillo;A. Damin;D. Gianolio;C. Lamberti;S. Bordiga;E. A. Quadrelli;J. Basset;G. Kervern;L. Emsley;G. Pintacuda;A. Zecchina
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文献类型：
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作者：
Jane Estephane;E. Groppo;J. Vitillo;A. Damin;D. Gianolio;C. Lamberti;S. Bordiga;E. A. Quadrelli;J. Basset;G. Kervern;L. Emsley;G. Pintacuda;A. Zecchina
顺磁固体核磁共振、扩展X射线吸收精细结构（EXAFS）和拉曼光谱，以及沿着采用不同密度泛函理论（DFT）进行的详细量子力学计算，成功地应用于研究分子孤立的二茂铬（Cp2Cr，其中Cp = C5H5）及其Cp2Cr（CO）加合物的磁性、结构和振动性质.顺磁性固体NMR明确地表明，自旋翻转发生从顺磁性Cp2Cr（三重态）到抗磁性Cp2Cr（CO）加合物（单重态），从而澄清了理论上的困境，不同的泛函之间的分歧，在预测最稳定的自旋状态。EXAFS和拉曼光谱能够在实验上区分单重态和三重态，因为不同的自旋状态对应于分子的不同几何形状，因此对应于不同的振动特征。这里报道的多技术方法可能有...
Paramagnetic solid-state NMR, extended X-ray absorption fine structure (EXAFS), and Raman spectroscopies, along with detailed quantum mechanical calculations performed with different density functional theory (DFT) functionals, are successfully applied to investigate the magnetic, structural, and vibrational properties of molecularly isolated chromocene (Cp2Cr, where Cp = C5H5) and of its Cp2Cr(CO) adduct. Paramagnetic solid-state NMR unequivocally demonstrates that a spin flip occurs by coming from the paramagnetic Cp2Cr (triplet state) to the diamagnetic Cp2Cr(CO) adduct (singlet state), thus clarifying the theoretical dilemma of the disagreement among different functionals in predicting the most stable spin state. EXAFS and Raman spectroscopies are able to experimentally discriminate between singlet and triplet states, because a different spin state corresponds to a different geometry of the molecule, and therefore to different vibrational features. The here reported multitechnique approach could have ...