Xi Lu, Jin Chao-Yi, Song Hong-Wei, Wang Xiao-Tong, Li Li-Cun, Sutter Jean-Pascal
Department of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.
Laboratoire de Chimie de Coordination du CNRS (LCC-CNRS), Université de Toulouse, CNRS, Toulouse, France.
Dalton Trans. 2022 May 3;51(17):6955-6963. doi: 10.1039/d2dt00220e.
Four novel heptanuclear Ln-Cu complexes with the formula [LnCu(hfac)(NITPhTzbis)][LnCu(hfac)(NITPhTzbis)] (LnCu = YCu 1, TbCu 2, DyCu 3 and HoCu 4; hfac = hexafluoroacetylacetonate) were successfully constructed by employing the triazole functionalized nitronyl nitroxide biradical ligand NITPh-Tzbis (NITPh-Tzbis = 5-(1,2,4-triazolyl)-1,3-bis(1'-oxyl-3'-oxido-4',4',5',5'-tetramethyl-4,5-hydro-1-imidazol-2-yl)benzene). These hetero-tri-spin complexes are composed of two biradical-bridged dinuclear [(LnCu(hfac)(NITPhTzbis)] units and one trinuclear [LnCu(hfac)(NITPhTzbis)] unit which form a heptanuclear supramolecular structure through π-π interactions. Magnetic susceptibility investigations indicate that ferromagnetic exchange interactions dominate at low temperature for this supramolecular system which can be attributed to the Ln-nitroxide exchange and intramolecular NIT⋯NIT coupling mediated by the -phenylene moiety. The DyCu derivative was found to exhibit a slow magnetic relaxation behavior.
通过使用三唑官能化的硝酰基氮氧化物双自由基配体NITPh-Tzbis（NITPh-Tzbis = 5-(1,2,4-三唑基)-1,3-双(1'-氧基-3'-氧化-4',4',5',5'-四甲基-4,5-氢-1-咪唑-2-基)苯），成功构建了四种新型的七核Ln-Cu配合物，其化学式为[LnCu(hfac)(NITPhTzbis)][LnCu(hfac)(NITPhTzbis)]（LnCu = YCu 1、TbCu 2、DyCu 3和HoCu 4；hfac = 六氟乙酰丙酮）。这些杂三自旋配合物由两个双自由基桥联的双核[(LnCu(hfac)(NITPhTzbis)]单元和一个三核[LnCu(hfac)(NITPhTzbis)]单元组成，它们通过π-π相互作用形成七核超分子结构。磁化率研究表明，对于该超分子体系，在低温下铁磁交换相互作用占主导，这可归因于Ln-氮氧化物交换以及由亚苯基部分介导的分子内NIT⋯NIT耦合。发现DyCu衍生物表现出慢磁弛豫行为。
