Origin of Long-Range Ferromagnetic Ordering in Metal鈥揙rganic Frameworks with Antiferromagnetic Dimeric-Cu(II) Building Units
详细信息 查看全文
- 作者：Lei Shen ; Shuo-Wang Yang ; Shengchang Xiang ; Tao Liu ; Bangchuan Zhao ; Man-Fai Ng ; J枚rg G枚ettlicher ; Jiabao Yi ; Sean Li ; Lan Wang ; Jun Ding ; Banglin Chen ; Su-Huai Wei ; Yuan Ping Feng
- 刊名：The Journal of the American Chemical Society
- 出版年：2012
- 出版时间：October 17, 2012
- 年：2012
- 卷：134
- 期：41
- 页码：17286-17290
- 全文大小：310K
- 年卷期：v.134,no.41(October 17, 2012)
- ISSN：1520-5126
文摘
Even though metal鈥搊rganic frameworks (MOFs) derived from antiferromagnetic dimeric-Cu(II) building units and nonmagnetic molecular linkers are known to exhibit unexpected ferromagnetic behavior, a comprehensive understanding of the underlying mechanism remains elusive. Using a combined theoretical and experimental approach, here we reveal the origin of the long-range ferromagnetic coupling in a series of MOFs, constructed from antiferromagnetic dimeric-Cu(II) building blocks. Our studies show that the strong localization of copper vacancy states favors spontaneous spin polarization and formation of local moment. These copper vacancy-induced moments are coupled via the itinerant electrons in the conjugated aromatic linkers to establish a long-range ferromagnetic ordering. The proposed mechanism is supported by direct experimental evidence of copper vacancies and the magnetic hysteresis (M-H) loops.