ランタノイド金属を含む低配位金属錯体から成る単一イオン磁石への計算化学的研究

我们提出的研究主题是使用计算工具对过渡金属（TM）和镧系（Ln）金属配合物的自旋-哈密顿参数（零场分裂（D）和g-张量）进行建模，以了解它们的单分子磁性（SMM）行为。在这方面，已经使用密度泛函理论（DFT）方法和B3 LYP功能对近三十种模型配合物进行了优化，例如Fe、Co和Ni的二价和三价金属配合物以及使用大体积配体的Ln（III）配合物。GAUSSIAN 16程序。这些优化研究是非常重要的，以测试所提出的理论协议，并在某些情况下，导致我们提出的策略更早的修订。在优化的分子中，我对四个分子进行了从头算CASSCF计算。对于两个Zn（II）-Ln（III）配合物，我已经从理论上证明了反磁性Zn（II）离子如何有助于提高镧系离子的能垒。对于两个Co（II）配合物，我试图了解它们的磁各向异性的起源，以实现其SMM行为。这些结果在这里进行了简要讨论。(i)Zn（II）-Ln（III）配合物（Ln = Dy（1）和Tb（2））：实验测量显示Dy配合物的SMM行为和Tb配合物的无SMM行为。(ii)Co（II）（单核（3）和双核（4））络合物：进行CASSCF计算以通过计算络合物3和4的g-和D-张量来合理化磁各向异性的起源，并计算4中Co离子之间的磁交换，进行DFT计算。

Our proposed research theme is modeling of spin-Hamiltonian parameters (zero-field splitting (D) and g-tensors) of transition metal (TM) and lanthanide (Ln) metal complexes using computational tools to understand their single-molecule magnetic (SMM) behavior. In this regard, nearly thirty model complexes such as two-, and three-coordinate divalent metal complexes of Fe, Co, and Ni, and Ln(III) complexes using bulky ligands have been optimized using Density Functional Theory (DFT) methods with B3LYP functional by GAUSSIAN 16 program. These optimization studies were very important to test the proposed theoretical protocols and, in some cases, lead to revision of our presented strategies earlier. Among the optimized molecules, I performed the ab initio CASSCF calculations on four molecules. For two Zn(II)-Ln(III) complexes, I have theoretically proven how a diamagnetic Zn(II) ion can help to enhance the energy barrier of lanthanide ions. For two Co(II) complexes, I have attempted to understand their origin of magnetic anisotropy in order to realize their SMM behavior. These results are discussed briefly here.(i) Zn(II)-Ln(III) complexes (Ln = Dy (1) and Tb (2)): Experimental measurement reveals SMM behavior for Dy complex and no SMM behavior for Tb complex.(ii) Co(II) (mononuclear (3) and dinuclear (4)) complexes: CASSCF calculations were performed to rationalize origin of magnetic anisotropy by computing g- and D-tensors for complexes 3 and 4 and to compute the magnetic exchange between the Co ions in 4, DFT calculations were performed.