title: Anions Influence the Relaxation Dynamics of Mono-μ3-OH-Capped Triangular Dysprosium Aggregates.
abstract: A family of four Dy3 triangular circular helicates, namely, [Dy3(HL)3(μ3-OH)(CH3OH)2(H2O)4]Cl1.5(OH)0.5·0.5H2O (1), [Dy3(HL)3(μ3-OH)(CH3OH)3(H2O)2Cl]Cl·CH3OH (2), [Dy3(HL)3(μ3-OH)(CH3OH)3(H2O)2(NO3)](NO3) (3), and [Dy3(HL)3(μ3-OH)(CH3OH)4(ClO4)](ClO4) (4), were assembled by the reaction of a new acylhydrazone ligand H3L [(3-hydroxy)-N'-((8-hydroxyquinolin-2-yl)methylene)picolinohydrazide] with different dysprosium(III) salts. These compounds represent the first examples of μ-Oacylhydrazone-bridged triangular Dy3 SMMs reported to date. Alternating-current magnetic susceptibility measurements revealed that compounds 1 and 2 show typical SMM behavior with the occurrence of multiple relaxation processes, whereas frequency-dependent relaxation signals without χ″ peaks were observed in 3 and 4 under zero dc field. Such distinct dynamic behaviors are attributed to the different sizes of the terminal coordination solvent/anions (H2O, Cl(-), NO3(-), and ClO4(-) for 1-4, respectively) at the Dy3 site. Here, similar deviations from the ideal monocapped square-antiprismatic (C4v) geometry defined by SHAPE software were observed around local Dy centers in 1 and 2, whereas the situation was completely different in 3 and 4 as a result of the presence of relatively large anions in the limited space defined by three intercrossing rigid hydrazone ligands.
authors.affiliation: †State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.|‡University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: †State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.|‡University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: †State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
authors.forename: Lang
authors.initials: L
authors.lastname: Zhao
authors.affiliation: †State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.|‡University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Wu
authors.affiliation: †State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.|‡University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
authors.forename: Mei
authors.initials: M
authors.lastname: Guo
authors.affiliation: †State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
authors.forename: Jinkui
authors.initials: J
authors.lastname: Tang