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

2021 Fiscal Year Annual Research Report

• Project/Area Number: 21F51029
• Research Institution: Tokyo Metropolitan University
• Principal Investigator: 波田 雅彦 東京都立大学, 理学研究科, 教授 (20228480)
• Co-Investigator(Kenkyū-buntansha): KUDUVA RADHAKRISHNAN VIGNESH 東京都立大学, 理学(系)研究科(研究院), 外国人特別研究員
• Project Period (FY): 2021-11-18 – 2023-03-31
• Keywords: 磁気物性 / 単分子磁石 / 金属錯体 / Spin-Hamiltonian

Outline of Annual Research Achievements

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.

Research Progress Status

翌年度、交付申請を辞退するため、記入しない。

Strategy for Future Research Activity

翌年度、交付申請を辞退するため、記入しない。