Vologzhanina Anna V, Kats Svitlana V, Penkova Larisa V, Pavlenko Vadim A, Efimov Nikolay N, Minin Vadim V, Eremenko Igor L
A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow 119991, Russian Federation.
Taras Shevchenko National University, Kiev UA-01601, Ukraine.
Acta Crystallogr B Struct Sci Cryst Eng Mater. 2015 Oct;71(Pt 5):543-54. doi: 10.1107/S2052520615015279. Epub 2015 Sep 30.
Interaction of 1-(1H-pyrazol-5-yl)ethanone oxime (H2PzOx) with copper(II) chloride in the presence of pyridine afforded a binuclear discrete [Cu2(HPzOx)2Cl2py2] complex, which was characterized by Fourier transform-IR and electron paramagnetic resonance (EPR) spectra, magnetochemistry and high-resolution X-ray diffraction experiments. Multipole refinement of X-ray diffraction data and density-functional theory (DFT) calculations of an isolated molecule allowed charge and spin distributions to be obtained for this compound. Magnetochemistry data, EPR spectra and DFT calculations of an isolated molecule show antiferromagnetic coupling between copper(II) ions. The spin distribution suggests an exchange pathway via the bridging pyrazole ring in the equatorial plane of the CuN4Cl coordination polyhedron, thus providing support for the classical superexchange mechanism; the calculated value of the magnetic coupling constant -2J is equal to 220 cm(-1), which compares well with the experimental value of 203 ± 2 cm(-1). Chemical connectivity was derived by Bader's 'quantum theory of atoms in molecules' and compared with Voronoi tessellation and Hirshfeld surface representations of crystal space. All methodologies gave a similar qualitative and semi-quantitative description of intra- and intermolecular connectivity.
在吡啶存在的情况下，1-(1H-吡唑-5-基)乙酮肟（H2PzOx）与氯化铜(II)相互作用，得到了双核离散型[Cu2(HPzOx)2Cl2py2]配合物，该配合物通过傅里叶变换红外光谱和电子顺磁共振（EPR）光谱、磁化学和高分辨率X射线衍射实验进行了表征。对X射线衍射数据进行多极精修以及对孤立分子进行密度泛函理论（DFT）计算，得以获得该化合物的电荷和自旋分布。孤立分子的磁化学数据、EPR光谱和DFT计算表明铜(II)离子之间存在反铁磁耦合。自旋分布表明，在CuN4Cl配位多面体的赤道平面中，通过桥连吡唑环存在一条交换途径，从而为经典的超交换机制提供了支持；磁耦合常数-2J的计算值等于220 cm(-1)，与203±2 cm(-1)的实验值相当。通过巴德的“分子中原子的量子理论”推导了化学连通性，并与晶体空间的沃罗诺伊镶嵌和赫希菲尔德表面表示进行了比较。所有方法对分子内和分子间连通性都给出了相似的定性和半定量描述。
