中国物理B ›› 2016, Vol. 25 ›› Issue (1): 17601-017601.doi: 10.1088/1674-1056/25/1/017601
• SPECIAL TOPIC—Soft matter and biological physics (Review) • 上一篇 下一篇
Ying Tian(田英), Shipeng Shen(申世鹏), Junzhuang Cong(丛君状), Liqin Yan(闫丽琴), Yisheng Chai(柴一晟), Young Sun(孙阳)
Ying Tian(田英), Shipeng Shen(申世鹏), Junzhuang Cong(丛君状), Liqin Yan(闫丽琴), Yisheng Chai(柴一晟), Young Sun(孙阳)
摘要:
The hybrid metal-organic framework [(CH3)2NH2]Fe(HCOO)3 with a perovskite-like structure exhibits a variety of unusual magnetic behaviors at low temperatures. While the long-distance super-exchange through the Fe-O-CH-O-Fe exchange path leads to a canted antiferromagnetic ordering at TN ~ 19 K, a second transition of magnetic blocking develops at TB ~ 9 K. The stair-shaped magnetization hysteresis loops below TB resemble the behaviors of resonant quantum tunneling of magnetization in single-molecular quantum magnets. Moreover, the magnetic relaxation also exhibits several features of resonant quantum relaxation, such as the exponential law with a single characteristic relaxation time, and the nonmonotonic dependence of relaxation rate on the applied magnetic field with a much faster relaxation around the resonant fields. The origin of quantum tunneling behaviors in the [(CH3)2NH2]Fe(HCOO)3 metal-organic framework is discussed in terms of magnetic phase separation due to the modification of hydrogen bonding on the long-distance super-exchange interaction.
中图分类号: (General theory of resonances and relaxations)