Construction of a General Library for the Rational Design of Nanomagnets and Spin Qubits Based on Mononuclear f-Block Complexes. The Polyoxometalate Case
Construction of a General Library for the Rational Design of Nanomagnets and Spin Qubits Based on Mononuclear f-Block Complexes. The Polyoxometalate Case
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DOI：
10.1021/ic501867d
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发表时间：
2014-09-15
影响因子：
4.6
通讯作者：
Gimenez-Saiz, Carlos
中科院分区：
文献类型：
--
作者：
Baldovi, Jose J.;Clemente-Juan, Juan M.;Gimenez-Saiz, Carlos
本文是一系列工作的一部分，旨在建立一个通用的文库，帮助描述任何配体对单核f元素配合物J基态分裂的晶场(CF)效应。在这里，通过对前两类基于稀土多金属氧酸盐(POMS)的单离子磁体的磁性能的研究，提取了与氧配体相关的有效参数(有效电荷和金属配位距离)，公式为[Ln(W5O18)(2)](9-)和[Ln(beta(2)-SiW11O39)(2)](13-)(Ln=Tb，Dy，Ho，Er，Tm，Yb)。这种有效的CF方法很好地描述了所研究体系的最低磁能级和相关波函数，这与观测到的磁行为完全一致。为了证明这个模型的预测特性，我们在第一步中扩展了我们的模型，计算了早期4f-块金属的POM络合物的性质。在此过程中，[Nd(W5O18)(2)](9-)被确定为表现SMM行为的合适候选者。磁性实验证实了这一预测，证明了这一策略在定向合成新的纳米磁体方面的有效性。因此，在1000Oe的外加直流磁场下，有效势垒为51.4厘米(-1)，这是第二个基于Nd3+的单离子磁体的例子。
This paper belongs to a series of contributions aiming at establishing a general library that helps in the description of the crystal field (CF) effect of any ligand on the splitting of the J ground states of mononuclear f-element complexes. Here, the effective parameters associated with the oxo ligands (effective charges and metalligand distances) are extracted from the study of the magnetic properties of the first two families of single-ion magnets based on lanthanoid polyoxometalates (POMs), formulated as [Ln(W5O18)(2)](9-) and [Ln(beta(2)-SiW11O39)(2)](13-) (Ln = Tb, Dy, Ho, Er, Tm, Yb). This effective CF approach provides a good description of the lowest-lying magnetic levels and the associated wave functions of the studied systems, which is fully consistent with the observed magnetic behavior. In order to demonstrate the predictive character of this model, we have extended our model in a first step to calculate the properties of the POM complexes of the early 4f-block metals. In doing so, [Nd(W5O18)(2)](9-) has been identified as a suitable candidate to exhibit SMM behavior. Magnetic experiments have confirmed such a prediction, demonstrating the usefulness of this strategy for the directed synthesis of new nanomagnets. Thus, with an effective barrier of 51.4 cm(-1) under an applied dc field of 1000 Oe, this is the second example of a Nd3+-based single-ion magnet.