Zhao Xiao-Qing, Xiang Shuo, Wang Jin, Bao Dong-Xu, Li Yun-Chun
College of Science Sichuan Agricultural University Ya'an 625014 P.R. China.
Key Laboratory of Advanced Energy Materials Chemistry, Ministry of Education Nankai University Tianjin 300071 P.R. China.
ChemistryOpen. 2018 Feb 2;7(2):192-200. doi: 10.1002/open.201700165. eCollection 2018 Feb.
Two 3-4 hetero-metal pentanuclear complexes with the formula {[CrLnL(OH)(HO)]EtNH} [Ln=Tb (), Dy (); HL=pivalic acid, EtN=triethylamine] have been produced. The metal core of each cluster is made up of a trigonal bipyramid with three Ln ions (plane) and two Cr ions (above and below) held together by six -OH bridges. Also reported with this series is the diamagnetic Cr-Y analogue (). Fortunately, we successfully prepared Al-Ln analogues with the formula {[AlLnL(OH)(HO)]EtNH⋅HO} [Ln=Tb (), Dy ()], containing diamagnetic Al ions, which can be used to evaluate the Cr-Ln magnetic nature through a diamagnetic substitution method. Subsequently, static (dc) magnetic susceptibility studies reveal dominant ferromagnetic interactions between Cr and Ln ions. Dynamic (ac) magnetic susceptibility studies show frequency-dependent out-of-phase ('') signals for [CrTb] (), [CrDy] (), and [AlDy] (), which are derived from the single-ion behavior of Ln ions and/or the Cr-Ln ferromagnetic interactions.
已制备出两种化学式为{[CrLnL(OH)(HO)]EtNH}的3 - 4异金属五核配合物[Ln = Tb (), Dy (); HL = 新戊酸, EtN = 三乙胺]。每个簇的金属核由一个三角双锥组成，其中三个Ln离子（平面）和两个Cr离子（上方和下方）通过六个 -OH桥连接在一起。该系列还报道了抗磁性的Cr - Y类似物()。幸运的是，我们成功制备了化学式为{[AlLnL(OH)(HO)]EtNH⋅HO} [Ln = Tb (), Dy ()]的Al - Ln类似物，其中含有抗磁性的Al离子，可通过抗磁性取代法用于评估Cr - Ln的磁性。随后，静态（直流）磁化率研究揭示了Cr和Ln离子之间主要的铁磁相互作用。动态（交流）磁化率研究表明，[CrTb] (), [CrDy] (), 和 [AlDy] ()存在频率依赖的异相（''）信号，这些信号源自Ln离子的单离子行为和/或Cr - Ln铁磁相互作用。
