Controlled Synthesis of Heterotrimetallic Single‐Chain Magnets from Anisotropic High‐Spin 3 d–4 f Nodes and Paramagnetic Spacers |
| |
| Authors: | Dr Min‐Xia Yao Qi Zheng Kang Qian Prof?Dr You Song Prof?Dr Song Gao Prof?Dr Jing‐Lin Zuo |
| |
| Institution: | 1. State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (P. R. China), Fax: (+86)?25‐83314502;2. School of Science, Nanjing University of Technology, Nanjing, 210009 (P. R. China);3. Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare‐Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (P. R. China) |
| |
| Abstract: | By using the node‐and‐spacer approach in suitable solvents, four new heterotrimetallic 1D chain‐like compounds (that is, containing 3d–3d′–4f metal ions), {Ni(L)Ln(NO3)2(H2O)Fe(Tp*)(CN)3] ? 2 CH3CN ? CH3OH}n (H2L=N,N′‐bis(3‐methoxysalicylidene)‐1,3‐diaminopropane, Tp*=hydridotris(3,5‐dimethylpyrazol‐1‐yl)borate; Ln=Gd ( 1 ), Dy ( 2 ), Tb ( 3 ), Nd ( 4 )), have been synthesized and structurally characterized. All of these compounds are made up of a neutral cyanide‐ and phenolate‐bridged heterotrimetallic chain, with a {? Fe? C?N? Ni(? O? Ln)? N?C? }n repeat unit. Within these chains, each (Tp*)Fe(CN)3]? entity binds to the NiII ion of the Ni(L)Ln(NO3)2(H2O)]+ motif through two of its three cyanide groups in a cis mode, whereas each Ni(L)Ln(NO3)2(H2O)]+ unit is linked to two (Tp*)Fe(CN)3]? ions through the NiII ion in a trans mode. In the Ni(L)Ln(NO3)2(H2O)]+ unit, the NiII and LnIII ions are bridged to one other through two phenolic oxygen atoms of the ligand (L). Compounds 1 – 4 are rare examples of 1D cyanide‐ and phenolate‐bridged 3d–3d′–4f helical chain compounds. As expected, strong ferromagnetic interactions are observed between neighboring FeIII and NiII ions through a cyanide bridge and between neighboring NiII and LnIII (except for NdIII) ions through two phenolate bridges. Further magnetic studies show that all of these compounds exhibit single‐chain magnetic behavior. Compound 2 exhibits the highest effective energy barrier (58.2 K) for the reversal of magnetization in 3d/4d/5d–4f heterotrimetallic single‐chain magnets. |
| |
| Keywords: | chain structures dysprosium heterometallic complexes lanthanides magnetism |
|
|
