N -oxide bridged manganese(II) coordination polymers
N -oxide bridged manganese(II) coordination polymers
复制标题
N-氧化物桥联锰(II)配位聚合物
DOI：
10.1080/00958970802621504
复制
发表时间：
2009
影响因子：
1.9
通讯作者：
J. Baruah
中科院分区：
文献类型：
--
作者：
R. Sarma;A. Perumal;J. Baruah
本文提出了一种合成具有不同苯甲酸酯配体和总组成为[Mn(RC6H4CO2)2(PYO)]n(其中PYO=吡啶N-氧化物且R=H，1a；R=4-NO2，1b；R=4-Cl，1c；R=4-OH，1d；R=2-NO2，1e)的锰(II)配位聚合物的简单方法。所有这些聚合物都用X射线结晶学和其他光谱技术进行了表征。配位聚合物具有相似的结构，但锰原子的位置不同。例如，1c是高度对称的，并且在每个锰位之间存在镜面(2/m)。在1D中，锰中心通过反转中心(−1)联系，而在1E中，锰中心通过C1旋转联系(1)。四水合醋酸锰(II)与4-氯苯甲酸反应，在甲醇/吡啶体系中结晶生成配位聚合物1c和双-4-氯苯甲酸锰(II)(2)。单晶X-射线衍射法也确定了化合物2的结构为一维氢键链结构。在20Oe和1000Oe下测量的1a-1c随温度变化的零场冷却和场冷却磁化强度数据表明，随场变化的磁化强度分布在5-300K的较宽温度范围内。这些配位聚合物在20K以下表现出反铁磁行为。
A simple method for synthesis of manganese(II) coordination polymers with different benzoate ligands and pyridine N-oxide having general composition [Mn(RC6H4CO2)2(PyO)] n is presented (where PyO = pyridine N-oxide and R = H, 1a; R = 4-NO2, 1b; R = 4-Cl, 1c; R = 4-OH, 1d; R = 2-NO2, 1e). All these polymers are characterized by X-ray crystallography and other spectroscopic techniques. The coordination polymers have similar structures, but the positions of the manganese atoms differ. For example, 1c is highly symmetric and a mirror plane exists between each manganese site (2/m). In 1d, the manganese centers are related by an inversion center (−1) whereas in 1e the manganese centers are related by C1 rotation (1). Reaction of manganese(II) acetate tetrahydrate with 4-chlorobenzoic acid and PyO upon crystallization from methanol/pyridine gave crystals of coordination polymer 1c along with aqua-bis-pyridine bis-4-chlorobenzoato manganese(II) (2). The structure of 2 also determined by single-crystal X-ray diffraction has a 1-D hydrogen bonded chain structure. Temperature-dependent zero-field cooled and field-cooled magnetization data of 1a–1c measured at 20 Oe and 1000 Oe show field-dependent magnetization spread over a wide temperature range from 5 to 300 K. These coordination polymers show anti-ferromagnetic behavior below 20 K.
倾斜蒸发Co-CoO磁记录带磁化强度的观察
DOI：
--
发表时间：
2006
期刊：
IEEE Transactions on Magnetics 42
影响因子：
--
作者：
W.X.Xia;et al.
通讯作者：
et al.