Angular-Resolved Magnetometry Beyond Triclinic Crystals Part II: Torque Magnetometry of Cp*ErCOT Single-Molecule Magnets
Angular-Resolved Magnetometry Beyond Triclinic Crystals Part II: Torque Magnetometry of Cp*ErCOT Single-Molecule Magnets
复制标题
DOI：
10.1002/chem.201404218
复制
发表时间：
2014-10-20
影响因子：
4.3
通讯作者：
Sessoli, Roberta
中科院分区：
文献类型：
--
作者：
Perfetti, Mauro;Cucinotta, Giuseppe;Sessoli, Roberta
用转矩磁强计研究了磁中心对称而不平行的晶体中分子磁各向异性的实验研究。正交有机金属Cp*ErCOT [Cp*=五甲基环戊二烯阴离子（C5Me5-）]的单晶在其阻滞温度以上，研究了以晶体中存在两个非平行分子族为特征的环四萜[C8H82-]单分子磁体。结果证实了ising型反各向异性，其容易方向指向配合物的伪对称轴，正如先前非平衡角分辨磁强计所提出的那样。使用扭矩磁强计，不需要磁滞的存在，证明是更强大的这些目的比标准单晶磁强计。此外，利用该技术的灵敏度和通用性，研究了高达150k的磁各向异性，提供了关于Er-III离子地面J倍体晶体场分裂的额外信息。
The experimental investigation of the molecular magnetic anisotropy in crystals in which the magnetic centers are symmetry related, but do not have a parallel orientation has been approached by using torque magnetometry. A single crystal of the orthorhombic organometallic Cp*ErCOT [Cp*=pentamethylcyclopentadiene anion (C5Me5-); COT = cyclooctatetraenedianion (C8H82-)] single-molecule magnet, characterized by the presence of two nonparallel families of molecules in the crystal, has been investigated above its blocking temperature. The results confirm an Ising-type ani-otropy with the easy direction pointing along the pseudosymmetry axis of the complex, as previously suggested by out-of-equilibrium angular-resolved magnetometry. The use of torque magnetometry, not requiring the presence of magnetic hysteresis, proves to be even more powerful for these purposes than standard single-crystal magnetometry. Furthermore, exploiting the sensitivity and versatility of this technique, magnetic anisotropy has been investigated up to 150 K, providing additional information on the crystal-field splitting of the ground J multiplet of the Er-III ion.