title: A family of 12-azametallacrown-4 structural motif with heterometallic Mn(III) -Ln-Mn(III) -Ln (Ln=Dy, Er, Yb, Tb, Y) alternate arrangement and single-molecule magnet behavior.
abstract: Mixed 3d-4f 12-azametallacrown-4 complexes, [Mn2 Ln2 (OH)2 (hppt)4 (OAc)2 (DMF)2 ]⋅2 DMF⋅H2 O [Ln=Dy (1), Er (2), Yb (3), Tb (4) and Y (5), H2 hppt=3-(2-hydroxyphenyl)-5-(pyrazin-2-yl)-1,2,4-triazole)], were synthesized by reactions of H2 hppt with Mn(OAc)2 ⋅4 H2 O and Ln(NO3 )3 ⋅6 H2 O. This is the first 3d-4f azametallacrown family to incorporate Ln ions into the ring sets. These isostructural complexes exhibit alternating arrangements of two Mn and two Ln ions in the rings with each pair of metal centers bound by an NN group and μ2 -O bridging. Magnetic measurements revealed dominant antiferromagnetic interactions between metal centers, and frequency-dependent out-of-phase (${\chi {^\prime}{^\prime}_{\rm{M}} }$) signals below 4 K suggest slow relaxation of magnetization.
authors: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng, 252059 (P.R. China).
authors: Hua
authors: H
authors: Yang
authors: State Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, 210093 Nanjing (P.R. China).
authors: Fan
authors: F
authors: Cao
authors: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng, 252059 (P.R. China).
authors: Dacheng
authors: D
authors: Li
authors: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng, 252059 (P.R. China).
authors: Suyuan
authors: S
authors: Zeng
authors: State Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, 210093 Nanjing (P.R. China). yousong@nju.edu.cn.
authors: You
authors: Y
authors: Song
authors: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng, 252059 (P.R. China). dougroup@163.com.
authors: Jianmin
authors: J
authors: Dou
keywords: N,O ligands; crown compounds; heterometallic complexes; magnetic properties; rare earths