| Autor: |
Le Roy JJ; Department of Chemistry, University of Ottawa , 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada., Ungur L, Korobkov I, Chibotaru LF, Murugesu M |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of the American Chemical Society [J Am Chem Soc] 2014 Jun 04; Vol. 136 (22), pp. 8003-10. Date of Electronic Publication: 2014 May 20. |
| DOI: |
10.1021/ja5022552 |
| Abstrakt: |
Two different coupling strategies were employed to create Er(III) single-molecule magnets (SMMs) using high blocking temperature mononuclear precursors. The magnetic properties of three lanthanide-COT complexes, [Er(III)2(COT'')3] (1) (COT'' = 1,4-bis(trimethylsilyl)cyclooctatetraenyl dianion) and K2(THF)4[Ln(III)2(COT)4] (Ln = Gd (2), Er (3); THF = tetrahydrofuran, COT = cyclooctatetraenyl dianion), are reported. Both Er(III) complexes behave as SMMs and exhibit magnetic hysteresis at 12 K in solid state. In solution compound 1 exhibits hysteresis up to 14 K. Ac susceptibility data indicates a 100 s blocking temperature of 12.5 and 12.9 K for [Er(III)2(COT'')3] and K2(THF)4[Er(III)2(COT)4], respectively. Both Er(III) dimers display enhanced SMM properties over their mononuclear analogues due to their linear structure and strictly axial anisotropy. A 4 K increase in the magnetic blocking temperature of [Er(III)2(COT'')3] over the double-decker analogue is attributed to an additional mechanism of magnetization blocking arising from exchange coupling between Er(III) ions. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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