Heteronuclear Ni(ii)–Ln(iii) (Ln = La, Pr, Tb, Dy) complexes: synthesis and single-molecule magnet behaviour

2016 ◽  
Vol 45 (8) ◽  
pp. 3616-3626 ◽  
Author(s):  
Apoorva Upadhyay ◽  
Chinmoy Das ◽  
Stuart K. Langley ◽  
Keith S. Murray ◽  
Anant K. Srivastava ◽  
...  

The crystal structures are reported for three heterometallic Ni2Ln and a Ni2Dy2 complex, using the Schiff base ligand 2-methoxy-6-[(E)-phenyliminomethyl] phenol. Detailed dc and ac magnetic susceptibility studies were reported for all the complexes. The complexes 3 and 4 shows frequency dependent out-of-phase susceptibility signals.

2018 ◽  
Vol 4 (4) ◽  
pp. 48
Author(s):  
Dimitris Alexandropoulos ◽  
Alysha Alaimo ◽  
Di Sun ◽  
Theocharis Stamatatos

A new {Dy5} cluster compound has been synthesized and structurally characterized from the initial use of the Schiff base ligand N-naphthalidene-2-amino-5-chlorophenol (nacpH2) in coordination chemistry. The 1:1 reaction between Dy(hpd)3∙2H2O and nacpH2, in a solvent mixture comprising CH2Cl2 and MeOH, afforded orange crystals of [Dy5(OH)2(hpd)3(nacp)5(MeOH)5] (1) in 70% yield, where hpd− is the anion of 3,5-heptadione. The {Dy5} complex can be described as two vertical {Dy3(μ3-OH)}8+ triangles sharing a common vertex; such a metal topology is unprecedented in 4f-metal cluster chemistry. Direct current (dc) magnetic susceptibility studies revealed the presence of some weak ferromagnetic exchange interactions between the five DyIII ions at low temperatures. Alternating current (ac) magnetic susceptibility measurements at zero applied dc field showed that complex 1∙3MeOH∙CH2Cl2 exhibits temperature- and frequency-dependent out-of-phase signals below ~20 K, characteristics of a single-molecule magnet (SMM). The resulting relaxation times were used to construct an Arrhenius-type plot and determine an effective energy barrier, Ueff, of 100 K for the magnetization reversal. The application of a small dc field of 200 Oe resulted in the surpassing of the quantum tunneling process and subsequently the increase of the Ueff to a value of 170 K. The reported results are part of a long-term program aiming at the preparation of structurally and magnetically interesting lanthanide complexes bearing various Schiff base chelating/bridging ligands.


2014 ◽  
Vol 58 (4) ◽  
pp. 650-657 ◽  
Author(s):  
Long Cui ◽  
Feifei Zhu ◽  
Chanel F. Leong ◽  
Jing Ru ◽  
Feng Gao ◽  
...  

2018 ◽  
Vol 5 (8) ◽  
pp. 1876-1885 ◽  
Author(s):  
Wen-Min Wang ◽  
Xiao-Min Kang ◽  
Hai-Yun Shen ◽  
Zhi-Lei Wu ◽  
Hong-Ling Gao ◽  
...  

Three Dy4 clusters based on a flexible and attractive Schiff base ligand HL have been synthesized, and they showed different tetranuclear core arrangements. Magnetic studies reveal that clusters 1–3 display distinct slow relaxation of magnetization.


2019 ◽  
Vol 43 (19) ◽  
pp. 7419-7426 ◽  
Author(s):  
Wen-Min Wang ◽  
Xian-Zhen Li ◽  
Li Zhang ◽  
Jia-Li Chen ◽  
Jun-Hua Wang ◽  
...  

Four new [2 × 2] square grid LnIII4 clusters were successfully synthesized by employing a multidentate chelating Schiff base ligand. Magnetic studies showed that cluster 1 displays a larger magnetocaloric effect (−ΔSm = 34.46 J kg−1 K−1 for ΔH = 7.0 T at 2.0 K), while 3 exhibits slow relaxation behavior under a zero dc field, with ΔE/kB of 42.76 K and τ0 of 1.02 × 10−6 s.


2019 ◽  
Vol 48 (44) ◽  
pp. 16744-16755 ◽  
Author(s):  
Wen-Min Wang ◽  
Li-Yuan He ◽  
Xin-Xin Wang ◽  
Ying Shi ◽  
Zhi-Lei Wu ◽  
...  

A series of linear-shaped LnIII4 and LnIII6 clusters were synthesized. The structures, fluorescence properties and magnetic properties have been deeply studied.


2017 ◽  
Vol 46 (8) ◽  
pp. 2471-2478 ◽  
Author(s):  
T. Lacelle ◽  
G. Brunet ◽  
A. Pialat ◽  
R. J. Holmberg ◽  
Y. Lan ◽  
...  

A tetranuclear dysprosium complex, bridged by a novel tetrazine-centered Schiff base ligand, exhibits ferromagnetic exchange coupling and a large anisotropic barrier.


Sign in / Sign up

Export Citation Format

Share Document