Slow Magnetic Relaxation Observed in Dysprosium Compounds Containing Unsupported Near-Linear Hydroxo- and Fluoro-Bridges
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- 作者：Gabriel Brunet ; Fatemah Habib ; Ilia Korobkov ; Muralee Murugesu
- 刊名：Inorganic Chemistry
- 出版年：2015
- 出版时间：July 6, 2015
- 年：2015
- 卷：54
- 期：13
- 页码：6195-6202
- 全文大小：573K
- ISSN：1520-510X
文摘
The encapsulating N1,N3-bis(3-methoxysalicylidene)diethylenetriamine (H2valdien) ligand was employed to isolate two novel DyIII compounds which contain rare bridging pathways for lanthanide systems. Compound 1, [Na2DyIII2(valdien)2(渭-OH)(dbm)2(H2O)2][Na2DyIII2(valdien)2(渭-OH)(NO3)2(dbm)2], where dbm鈥?/sup> is dibenzoylmethanido, and compound 2, [Na3DyIII2(valdien)2(渭-F)(渭3-F)2(Cl)2(MeOH)2]n路0.5(MeOH)路(H2O), both exhibit linear lone hydroxo- and fluoro-bridges, respectively, between the metal centers. The unit cell of 1 comprises two discrete dinuclear molecules, which differ slightly, forming a cation鈥揳nion pair, while 2 forms a coordination polymer. The magnetic investigations indicate that both compounds display ferromagnetic coupling between the DyIII ions. Magnetic susceptibility measurements in the temperature range 1.8鈥?00 K reveal that the DyIII ions in 1 are weakly coupled, resulting in a mononuclear single-molecule magnet-like behavior under an applied field. In the case of 2, the stronger coupling arising from the fluoride-bridge, leads to zero-field single-molecule magnet (SMM) behavior with a non-negligible anisotropy barrier (Ueff) of 42 K.