Heteroleptic iron complexes with a naphthoquinone-type ligand, 2-(pyridin-2-yl)-1H-naphtho[2,3-d]imidazole-4,9-dione (HL), were synthesized, and their structures and magnetic properties were investigated. Two spin-crossover complexes, [Fe(L)2(L1)] (1, L1 = ethylenediamine) and [Fe(L)2(L2)] (2, L2 = cyclohexanediamine) were structurally characterized at 100 K and 270 K, and their gradual spin crossover behavior observed by magnetic susceptibility measurements and confirmed by Mössbauer spectroscopic analyses. Two homologous iron(ii) complexes, [Fe(L)2(L3c)] (3, L3c = diimino benzoquinone) and [Fe(L)2(L4c)] (4, L4c = iminosuccinonitrile), were found to exist in the low-spin state in the range of 10-300 K. In contrast, the corresponding complex with two water ligands, [Fe(L)2(H2O)2] (5), and the tris-chelate complex with protonated ligands (HL), [Fe(HL)3](BF4)2 (6), were found to be high-spin.

中文翻译：

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杂萘铁与萘醌型配体的配合物。

合成了具有萘醌型配体2-（吡啶-2-基）-1H-萘[2,3-d]咪唑-4,9-二酮（HL）的杂多铁配合物，其结构和磁性被调查了。[Fe（L）2（L1）]（1，L1 =乙二胺）和[Fe（L）2（L2）]（2，L2 =环己二胺）两种自旋交联络合物的结构特征分别为100 K和270 K ，并通过磁化率测量观察到它们的逐渐自旋交叉行为，并由Mössbauer光谱分析证实。发现在其中存在两种同源铁（ii）络合物[Fe（L）2（L3c）]（3，L3c =二亚氨基苯醌）和[Fe（L）2（L4c）]（4，L4c =亚氨基琥珀腈）。相反，具有两个水配体[Fe（L）2（H2O）2]（5）的相应络合物和具有质子化配体的三螯合物（ HL），