Density Functional Theory Study on the 193Ir Moessbauer Spectroscopic Parameters of Vaska’s Complexes and Their Oxidative Adducts
Density Functional Theory Study on the 193Ir Moessbauer Spectroscopic Parameters of Vaska’s Complexes and Their Oxidative Adducts
复制标题
Vaska配合物及其氧化加合物的193Ir穆斯堡尔光谱参数的密度泛函理论研究
DOI：
10.1021/acs.inorgchem.1c00239
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发表时间：
2021
影响因子：
4.6
通讯作者：
Nakashima Satoru
中科院分区：
文献类型：
--
作者：
Kaneko Masashi;Nakashima Satoru
在本研究中，密度泛函理论（DFT）计算应用于Vaska配合物的formulatranans -[IrIX(CO)(PPh3)2]及其氧化加合物与小分子（YZ）包括H2，即反式-[IrIIIClYZ(CO)(PPh3)2]，成功地将配合物的电子态与相应的193ir Mössbauer光谱参数关联起来。在确认了DFT方法对八面体Ir配合物的平衡结构和193ir Mössbauer异构体位移的再现性后，计算了Vaska配合物及其氧化加合物的异构体位移和四极分裂值。键临界点分析表明，同分异构体位移的趋势与配位键中共价相互作用的强度有关。在氧化加合物的电场梯度（EFG）分析中，发现YZ = cl2配合物的主轴符号为正，而YZ = H2配合物的主轴符号为负。根据态密度分析，这种EFG主轴符号的反转是由Ir和YZ之间配位键的电子密度分布的差异引起的。
In the present study, density functional theory (DFT) calculation was applied to Vaska’s complexes of formulatrans-[IrIX(CO)(PPh3)2] and their oxidative adducts with small molecules (YZ) including H2, i.e.,trans-[IrIIIClYZ(CO)(PPh3)2], to successfully correlate the electronic states of the complexes with the corresponding193Ir Mössbauer spectroscopic parameters. After confirming the reproducibility of the DFT methods for elucidating the equilibrium structures and193Ir Mössbauer isomer shifts of the octahedral Ir complexes, the isomer shifts and quadrupole splitting values of Vaska’s complexes and their oxidative adducts were calculated. A bond critical point analysis revealed that the tendency in the isomer shifts was correlated with the strength of the covalent interaction in the coordination bonds. In an electric field gradient (EFG) analysis of the oxidative adducts, the sign of the principal axis was found to be positive for the complex with YZ = Cl2and negative for the complex with YZ = H2. This reversal of the sign of the EFG principal axis was caused by the difference in the electron density distribution for the coordination bonds between Ir and YZ, according to a density of states analysis.