Yin Dan-Dan, Chen Qi, Meng Yin-Shan, Sun Hao-Ling, Zhang Yi-Quan, Gao Song
Department of Chemistry and Beijing Key Laboratory of Energy Conversion and Storage Materials , Beijing Normal University , Beijing 100875 , P. R. China . Email:
Beijing National Laboratory for Molecular Sciences , State Key Laboratory of Rare Earth Materials Chemistry and Applications , College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China . Email:
Chem Sci. 2015 May 1;6(5):3095-3101. doi: 10.1039/c5sc00491h. Epub 2015 Mar 17.
A new 2D dysprosium layer compound has been successfully synthesized from reaction with 2-(3-pyridyl) pyrimidine-4-carboxylic acid (H3-py-4-pmc), in which the Dy ions reside in square antiprismatic coordination environments and are connected by carboxylate/oxalate/hydroxyl bridges. Magnetic studies reveal ferromagnetic interactions between Dy ions, slow magnetic relaxation with an effective energy barrier of 186 K under zero dc field and pronounced hysteresis loops at low temperatures. Further dilution magnetic study suggests that the slow magnetic relaxation originates from the single-ion magnetic behavior of Dy ion and that magnetic coupling suppresses the quantum tunneling of magnetization at low temperature. In addition, theoretical calculation indicates strong Ising anisotropy of the Dy ion that is due to the strong interaction between Dy ions and hydroxyl groups.
通过与2-(3-吡啶基)嘧啶-4-羧酸（H3-py-4-pmc）反应，成功合成了一种新型二维镝层状化合物，其中镝离子处于方形反棱柱配位环境中，并通过羧酸盐/草酸盐/羟基桥相连。磁性研究表明，镝离子之间存在铁磁相互作用，在零直流场下具有186 K的有效能垒的慢磁弛豫以及在低温下明显的磁滞回线。进一步的稀释磁性研究表明，慢磁弛豫源于镝离子的单离子磁行为，并且磁耦合在低温下抑制了磁化的量子隧穿。此外，理论计算表明，由于镝离子与羟基之间的强相互作用，镝离子具有很强的伊辛各向异性。
