Anionic NaCl-type frameworks of [MnII(HCOO)3-], templated by alkylammonium, exhibit weak ferromagnetism
Anionic NaCl-type frameworks of [MnII(HCOO)3-], templated by alkylammonium, exhibit weak ferromagnetism
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DOI：
10.1039/b404466e
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发表时间：
2004-01-01
影响因子：
4
通讯作者：
Kurmoo, M
中科院分区：
文献类型：
--
作者：
Wang, ZM;Zhang, B;Kurmoo, M
本文报道了一系列以烷基铵为模板剂的新型NaCl型骨架化合物[AmineH（+）][Mn（HCOO）（3）（-）]的合成、红外光谱、热重分析、单晶X-射线结构和磁性。[Mn（HCOO）（3）（-）]的阴离子NaCl骨架被位于骨架空腔中的烷基铵阳离子抵消，烷基铵阳离子与骨架空腔氢键合。二价锰离子具有八面体几何形状，并以反-反配位模式通过甲酸根桥接。所有的化合物表现出长程反铁磁性低于9 K的轻微的非共线排列的时刻。倾斜，可能是由于二阶自旋轨道耦合，是通过Dzyaloshinski-Moriya反对称交换机制。在每种情况下，在相当低的磁场下都观察到自旋翻转。一个正交单斜晶系的转变，观察质子化的环三亚甲基胺，伴随着本地化的阳离子到两个位置低于240 K从快速动态翻转的环在室温下观察到。
We present the synthesis, characterization by IR, TGA, single crystal X-ray structure and magnetic properties of a novel series of NaCl-type frameworks of [AmineH(+)][Mn(HCOO)(3)(-)], templated by alkylammonium. The anionic NaCl-framework of [Mn(HCOO)(3)(-)] is counter-balanced by the alkylammonium cations located in the cavities of the framework to which they are hydrogen-bonded. The divalent manganese ions have octahedral geometry and are bridged by the formate in an anti-anti mode of coordination. All the compounds exhibit long-range antiferromagnetism below 9 K with a slight non-collinear arrangement of the moments. The canting, likely due to second-order spin-orbit coupling, is via a Dzyaloshinski-Moriya antisymmetric exchange mechanism. A spin-flop is observed in each case at fairly low fields. An orthorhombic to monoclinic transformation was observed for the protonated cyclotrimethyleneamine that is accompanied by localization of the cations into two positions below 240 K from the rapid dynamic flipping of the ring observed at room temperature.