Anorganisch-Chemisches Institut, INF 270, Universität Heidelberg, D-69120 Heidelberg, Germany.
Inorg Chem. 2012 Sep 3;51(17):9357-68. doi: 10.1021/ic301122h. Epub 2012 Aug 20.
We report here the synthesis and characterization of four dinuclear cyanide-bridged Fe(III)-Cu(II) complexes, based on a tetra- or a pentadentate bispidine ligand (L(1) or L(2), respectively; bispidines are 3,7-diazabiyclo[3.3.1]nonane derivatives) coordinated to the Cu(II) center, and a tridentate bipyridineamide (bpca) coordinated to the low-spin Fe(III) site, with cyanide groups completing the two coordination spheres, one of them bridging between the two metal ions. The four structurally characterized complexes [{Fe(bpca)(CN)(3)}{Cu(L(1)·H(2)O)}]BF(4), [{Fe(bpca)(CN)(3)}{Cu(L(2))}][Fe(bpca)(CN)(3)]·5H(2)O, [{Fe(bpca)(CN)(3)}{Cu(L(2)·MeOH)}]PF(6)·MeOH·H(2)O, and [{Fe(bpca)(CN)(3)}{Cu(L(2))}]PF(6)·2H(2)O belong to different structural isomers. The most important differences are structurally and electronically enforced (direction of the pseudo-Jahn-Teller mode) strong or weak interactions of the copper(II) center with the cyanide bridge. The related strength of the magnetic coupling of the two centers is analyzed with a combination of experimental magnetic, electron paramagnetic resonance (EPR), electronic spectroscopic data together with a ligand-field theory- and density functional theory (DFT)-based analysis.
我们在此报告了基于四齿或五齿双吡啶配体（L(1)或 L(2)，分别为 3,7-二氮杂双环[3.3.1]壬烷衍生物）配位到 Cu(II)中心，以及一个三齿联吡啶酰胺（bpca）配位到低自旋 Fe(III)位点的四个双核氰桥 Fe(III)-Cu(II)配合物的合成和表征，氰根基团完成两个配位场，其中一个将两个金属离子桥接。四个结构表征的配合物 [{Fe(bpca)(CN)(3)}{Cu(L(1)·H(2)O)}]BF(4)，[{Fe(bpca)(CN)(3)}{Cu(L(2))}][Fe(bpca)(CN)(3)]·5H(2)O，[{Fe(bpca)(CN)(3)}{Cu(L(2)·MeOH)}]PF(6)·MeOH·H(2)O 和 [{Fe(bpca)(CN)(3)}{Cu(L(2))}]PF(6)·2H(2)O 属于不同的结构异构体。最重要的区别是铜(II)中心与氰桥之间的结构和电子强制（伪 Jahn-Teller 模式的方向）强或弱相互作用。两个中心的磁耦合相关强度通过结合实验磁性、电子顺磁共振（EPR）、电子光谱数据以及基于配体场理论和密度泛函理论（DFT）的分析进行了分析。
