Canaj Angelos B, Dey Sourav, Martí Emma Regincós, Wilson Claire, Rajaraman Gopalan, Murrie Mark
WestCHEM, School of Chemistry, University of Glasgow, University Avenue, Glasgow, G12 8QQ, UK.
Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, 400076, India.
Angew Chem Int Ed Engl. 2019 Oct 1;58(40):14146-14151. doi: 10.1002/anie.201907686. Epub 2019 Aug 22.
Following a novel synthetic strategy where the strong uniaxial ligand field generated by the Ph SiO (Ph SiO =anion of triphenylsilanol) and the 2,4-di- Bu-PhO (2,4-di- Bu-PhO =anion of 2,4-di-tertbutylphenol) ligands combined with the weak equatorial field of the ligand L , leads to Dy (L )(2,4-di- Bu-PhO) (1), Dy (L )(Ph SiO) (2) and Dy (L )(Ph SiO) (3) hexagonal bipyramidal dysprosium(III) single-molecule magnets (SMMs) with high anisotropy barriers of U =973 K for 1, U =1080 K for 2 and U =1124 K for 3 under zero applied dc field. Ab initio calculations predict that the dominant magnetization reversal barrier of these complexes expands up to the 3rd Kramers doublet, thus revealing for the first time the exceptional uniaxial magnetic anisotropy that even the six equatorial donor atoms fail to negate, opening up the possibility to other higher-order symmetry SMMs.
遵循一种新颖的合成策略，其中由PhSiO（PhSiO =三苯基硅醇阴离子）和2,4 - 二 - Bu - PhO（2,4 - 二 - Bu - PhO = 2,4 - 二叔丁基苯酚阴离子）配体产生的强单轴配体场与配体L的弱赤道场相结合，得到Dy(L)(2,4 - 二 - Bu - PhO)（1）、Dy(L)(PhSiO)（2）和Dy(L)(PhSiO)（3）六方双锥镝（III）单分子磁体（SMM），在零直流外场下，1的各向异性势垒U = 973 K，2的U = 1080 K，3的U = 1124 K。从头算计算预测，这些配合物的主要磁化反转势垒扩展到第三个克莱默斯二重态，从而首次揭示了即使六个赤道供体原子也无法消除的异常单轴磁各向异性，为其他高阶对称SMM开辟了可能性。
