Yamato Keisuke, Kanetomo Takuya, Enomoto Masaya
Department of Chemistry, Faculty of Science Division I, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan.
ACS Omega. 2025 Jan 16;10(3):3182-3189. doi: 10.1021/acsomega.4c10686. eCollection 2025 Jan 28.
Terpyridine-based cobalt(II) complex, [Co(HL)] (; HL = 2,2':6',2″-terpyridine-5,5″-diyl dicarboxylic acid), forms a hydrogen-bonded diamond framework with solvent absorption and desorption capabilities. The desolvated form (·desolv) exhibits spin transition (ST) behavior accompanied by thermal hysteresis. To investigate the effect of metal-dilution, an Fe center, which has a low-spin state ( = 0) and coordinates to two terpyridine moieties, was introduced. The resulting complexes, [Co Fe (HL)], where = 0.88 (), 0.55 (), and 0 (), demonstrated a significant influence of metal-dilution on the desolvated forms, but not on the solvated forms. Namely, the spin state is more strongly affected by the presence of solvent than by metal-dilution. However, in the absence of solvent, the Fe ratio significantly impacts the ST behavior.
基于三联吡啶的钴（II）配合物[Co(HL)]（HL = 2,2':6',2″-三联吡啶-5,5″-二羧酸）形成了具有溶剂吸收和解吸能力的氢键菱形框架。去溶剂化形式（·desolv）表现出自旋转变（ST）行为并伴有热滞现象。为了研究金属稀释的影响，引入了一个处于低自旋态（S = 0）且与两个三联吡啶部分配位的铁中心。所得配合物[CoₓFe₁₋ₓ(HL)]，其中x = 0.88（1）、0.55（2）和0（3），表明金属稀释对去溶剂化形式有显著影响，但对溶剂化形式没有影响。也就是说，自旋态受溶剂存在的影响比金属稀释的影响更大。然而，在没有溶剂的情况下，铁的比例对自旋转变行为有显著影响。
