Single-molecule magnetism in a pentacoordinate cobalt(II) complex supported by an antenna ligand.
Single-molecule magnetism in a pentacoordinate cobalt(II) complex supported by an antenna ligand.
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DOI：
10.1021/ic501524a
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发表时间：
2014-08
影响因子：
4.6
通讯作者：
C. Rajnák;J. Titiš;O. Fuhr;M. Ruben;R. Boča
中科院分区：
文献类型：
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作者：
C. Rajnák;J. Titiš;O. Fuhr;M. Ruben;R. Boča
五配位络合物[CoL（3）Cl 2]与三齿天线样配体L（3）形成二聚体，该二聚体通过短π-π堆积与3.4 π处的头对头接触保持。直流（dc）磁化率和磁化强度数据证实弱铁磁相互作用和大的磁各向异性，D/hc = 150 cm（-1）和E/hc = 11.6 cm（-1）。该系统在低温下表现出超顺磁性行为，这取决于所施加的磁场。在Bdc = 0.2 T时，在异相磁化率处出现低频峰（ν <0.3 Hz），而第二个峰出现在ν > 1500 Hz时，表明存在两个慢弛豫过程。
Pentacoordinate complex [CoL(3)Cl2] with a tridentate antenna-like ligand L(3) forms a dimer held by short π-π stacking with head-to-head contacts at 3.4 Å. The direct-current (dc) magnetic susceptibility and magnetization data confirm weak ferromagnetic interaction and a large-magnetic anisotropy, D/hc = 150 cm(-1) and E/hc = 11.6 cm(-1). The system shows superparamagnetic behavior at low temperature that depends upon the applied magnetic field. At Bdc = 0.2 T, a low-frequency peak at the out-of-phase susceptibility is seen (ν ∼ 0.3 Hz), whereas the onset of the second peak appears at ν > 1500 Hz, indicating the existence of two slow relaxation processes.