Single-ion magnets with D-4d symmetry based on electron-donating beta-diketonate Dy(iii) complexes
Single-ion magnets with D-4d symmetry based on electron-donating beta-diketonate Dy(iii) complexes
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基于给电子 β-二酮 Dy(iii) 配合物的具有 D-4d 对称性的单离子磁体
DOI：
10.1039/c8nj00636a
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发表时间：
2018
影响因子：
3.3
通讯作者：
Li Guangming
中科院分区：
文献类型：
--
作者：
Yao Xu;Yan Pengfei;An Guanghui;Shi Chao;Li Yuxin;Li Guangming
四个单核镝配合物，即[Dy（thd）3（MeOH）2]（1），[Dy（thd）3（Phen）]（2），[Dy（thd）3（Dpq）]（3）和[Dy（thd）3（Dppz）]（4）（thd = 2，2，6，6-四甲基-3，5-庚二酮; Phen = 1，10-菲咯啉; Dpq =二吡嗪[2，3-f：2′，3 ′-h]喹喔啉; Dppz =二吡啶并[3，2-a：2′，3 ′-c]吩嗪），通过Hthd与DyCl 3·6 H2 O及相应的辅助封端配体Phen，Dpq和Dppz反应，合成了一系列新的化合物。晶体结构分析表明，配合物1-4中Dy（III）离子呈畸变正方反棱柱构型，具有D4 d对称性。磁性分析表明，配合物1-4均表现出缓慢的磁弛豫，势垒高度（Ueff/kB）分别为45.1K、98.4K、128.9K和89.4K。蝶形磁滞回线观察到高达5 K的复杂2。讨论了Dy-Oβ-二酮键长、量化畸变度（σα2或σΦ2）和磁易轴偏离角（θ）与SAP配位环境势垒高度的关系。
Four mononuclear dysprosium complexes, namely, [Dy(thd)3(MeOH)2] (1), [Dy(thd)3(Phen)] (2), [Dy(thd)3(Dpq)] (3) and [Dy(thd)3(Dppz)] (4) (thd = 2,2,6,6-tetramethyl-3,5-heptanedione; Phen = 1,10-phenanthroline; Dpq = dipyrazine[2,3-f:2′,3′-h]quinoxaline; and Dppz = dipyrido[3,2-a:2′,3′-c]phenazine), have been designed and isolated by reactions of Hthd with DyCl3·6H2O and corresponding auxiliary capping ligands such as Phen, Dpq and Dppz. The crystal structure analysis exhibits that Dy(III) ions in complexes 1–4 adopt distorted square antiprism geometry with D4d symmetry. Magnetic analysis reveals that all complexes 1–4 exhibit slow magnetic relaxation with the barrier heights (Ueff/kB) of 45.1 K, 98.4 K, 128.9 K and 89.4 K, respectively. The butterfly magnetic hysteresis loops were observed up to 5 K for complex 2. The co-relationship between the barrier heights and the structure in terms of the Dy–Oβ-diketone bond lengths, the quantify distortion degree (σα2 or σΦ2) and the deviation angles (θ) of magnetic easy axes for the SAP coordination environment were investigated and discussed.