Synthesis and reaction of [{HC(CMeNAr)2}Mn]2 (Ar=2,6-iPr2C6H3):: The complex containing three-coordinate manganese(I) with a Mn-Mn bond exhibiting unusual magnetic properties and electronic structure
Synthesis and reaction of [{HC(CMeNAr)2}Mn]2 (Ar=2,6-iPr2C6H3):: The complex containing three-coordinate manganese(I) with a Mn-Mn bond exhibiting unusual magnetic properties and electronic structure
复制标题
DOI：
10.1021/ja042269e
复制
发表时间：
2005-06-29
影响因子：
15
通讯作者：
Gatteschi, D
中科院分区：
文献类型：
--
作者：
Chai, JF;Zhu, HP;Gatteschi, D
本文报道了第一个三配位锰配合物[{HC(CMeNAr)(2)}Mn](2)(Ar=2，6-ipr(2)C(6)H(3))(2)的合成、X-射线结构、磁性和密度泛函理论计算(L)。在甲苯中用Na/K还原碘化物[{HC(CMeNAr)(2)}Mn(Mu-L)](2)(1)，得到暗红色晶体2。分子2含有一个具有Mn-Mn键的Mn-2(2+)核。磁性研究表明，这是一个罕见的高自旋锰(L)络合物，它的两个锰(L)中心之间存在反铁磁相互作用。密度泛函理论计算表明，具有开壳组态(3d(5)4s(1))的两个Mn(L)离子之间存在较强的S-S相互作用。这表明，2的磁性行为可以正确地描述为两个S-1=S-2=(5)/(2)自旋中心之间的耦合。用B3LYP泛函进行第一性原理计算，估算出Mn-Mn键能为44kcal mol(-1)。2与KMnO4或02进一步氧化反应生成氧化锰[{HC(CMeNAr)(2)}Mn(Mu-O)](2)(3)。通过磁性测量，化合物3显示了两个氧桥联的锰(III)中心之间的反铁磁耦合。
This paper reports on the synthesis, X-ray structure, magnetic properties, and DFT calculations of [{HC(CMeNAr)(2)}Mn](2) (Ar = 2,6-iPr(2)C(6)H(3)) (2), the first complex with three-coordinate manganese(l). Reduction of the iodide [{HC(CMeNAr)(2)}Mn(mu-l)](2) (1) with Na/K in toluene afforded 2 as dark-red crystals. The molecule of 2 contains a Mn-2(2+) core with a Mn-Mn bond. The magnetic investigations show a rare example of a high-spin manganese(l) complex with an antiferromagnetic interaction between the two Mn(l) centers. The DFT calculations indicate a strong s-s interaction of the two Mn(l) ions with the open shell configuration (3d(5)4s(1)). This suggests that the magnetic behavior of 2 could be correctly described as the coupling between two S-1 = S-2 = (5)/(2) spin centers. The Mn-Mn bond energy is estimated at 44 kcal mol(-1) by first principle calculations with the B3LYP functional. The further oxidative reaction of 2 with KMnO4 or 02 resulted in the formation of manganese(III) oxide [{HC(CMeNAr)(2)}Mn(mu-O)](2) (3). Compound 3 shows an antiferromagnetic coupling between the two oxo-bridged manganese(III) centers by magnetic measurements.