盘状镝簇合物的合成及缓慢磁弛豫  

Synthesis and Slow Magnetic Relaxation of a Disc-like Dysprosium Cluster

作　　者：卫晓琴 张凤英 李万喜 王新益 张爱华[3] 刘毓芳[3] WEI Xiao-Qin;ZHANG Feng-Ying;LI Wan-Xi;WANG Xin-Yi;ZHANG Ai-Hua;LIU Yu-Fang(Shanxi Province Collaborative Innovation Center for Light Materials Modification and Application,Department of Material Science and Engineering,Jinzhong University,Jinzhong,Shanxi 030619,China;State Key Laboratory of Coordination Chemistry,School of Chemistry and Chemical Engineering,Nanjing University,Nanjing 210023,China;Department of Chemistry and Chemical Engineering,Jinzhong University,Jinzhong,Shanxi 030619,China)

机构地区：[1]晋中学院材料科学与工程系,山西省轻质材料改性应用协同创新中心,晋中030619 [2]南京大学化学化工学院,配位化学国家重点实验室,南京210023 [3]晋中学院化学化工系,晋中030619

出　　处：《无机化学学报》2022年第7期1382-1390,共9页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.21973039);山西省基础研究计划(自由探索类)项目(No.20210302123355);山西省高等学校科技创新项目(No.2020L0592);晋中学院“1331工程”新型催化材料创新团队项目(No.jzxycxtd2019005);晋中学院博士基金项目(No.jzxybsjjxm2019020)资助。

摘　　要：利用稀土盐DyCl_(3)·6H_(2)O、双齿配体tmphen和[Mo^(Ⅲ)(CN)_(7)]^(4-)构筑块自组装得到镝的七核团簇化合物:[Dy^(Ⅲ)_(7)(tmphen)_(12)O_(6)(OH)_(6)Cl_(2)][Mo^(Ⅵ)(tmphen)O(CN)_(3)]_(6)Cl_(7)·66H_(2)O(1,tmphen=3,4,7,8-四甲基-1,10-菲咯啉),并对其进行了结构和磁性表征。晶体结构表明,化合物1的主体为七核镝形成的圆盘状结构,而[Mo^(Ⅲ)(CN)_(7)]^(4-)构筑块发生了氧化分解,形成了[Mo^(Ⅵ)(tmphen)O(CN)_(3)]^(+)阳离子游离在晶格中。直流磁化率表明化合物由于存在量子隧穿弛豫路径,在低温下没有出现磁滞回线。交流磁化率表明,该化合物在零场下表现出缓慢磁弛豫的现象,具有单分子磁体的性质,其有效能垒为51.6 K(35.8 cm^(-1),τ_(0)=17μs)。By using rare earth salt of DyCl_(3)·6H_(2)O, a bidentate ligand of tmphen and the block of [Mo^(Ⅲ)(CN)_(7)]^(4-),a dysprosium heptanuclear cluster was self-assembled with the formula of [Dy^(Ⅲ)_(7)(tmphen)_(12)O_(6)(OH)_(6)Cl_(2)][Mo^(Ⅵ)(tmphen)O(CN)_(3)]_(6)Cl_(7)·66H_(2)O(1, tmphen=3,4,7,8-tetramethyl-1,10-phenanthroline), which was characterized structurally and magnetically. The crystal structure shows that compound 1 is dominated by a disc-like structure of dysprosium heptanuclear. The [Mo^(Ⅲ)(CN)_(7)]^(4-) block was oxidized and decomposed, forming [Mo^(Ⅵ)(tmphen)O(CN)_(3)]^(+)cations free in the lattice. Besides, weak π-π interactions are found between aromatic rings of tmphen. The direct-current(dc) magnetic susceptibility indicated this compound had no hysteresis loop at low temperatures due to the existence of the quantum tunneling relaxation path. The alternating current(ac) magnetic susceptibility, however, illustrated that the compound exhibited slow magnetic relaxation under zero field, showing the properties of a single-molecule magnet,with an effective barrier of 51.6 K(35.8 cm^(-1), τ_(0)=17 μs). CCDC: 2161872.

关 键 词：镝 多核团簇 磁各向异性 单分子磁体 磁弛豫 

分 类 号：O614.342[理学—无机化学]