The reaction of a Schiff base ligand (LH3) with lanthanide salts, pivalic acid and triethylamine in 1:1:1:3 and 4:5:8:20 stoichiometric ratios results in the formation of decanuclear Ln10 (Ln = Dy (1), Tb (2), and Gd (3)) and pentanuclear Ln5 complexes (Ln = Gd (4), Tb (5), and Dy (6)), respectively. The formation of Ln10 and Ln5 complexes are fully governed by the stoichiometry of the reagents used. Detailed magnetic studies on these complexes (1-6) have been carried out. Complex 1 shows a SMM behavior with an effective energy barrier for the reversal of the magnetization (Ueff) = 16.12(8) K and relaxation time (τo) = 3.3×10(-5) s under 4000 Oe direct current (dc) field. Complex 6 shows the frequency dependent maxima in the out-of-phase signal under zero dc field, without achieving maxima above 2 K. Complexes 3 and 4 show a large magnetocaloric effect with the following characteristic values: -ΔSm = 26.6 J kg(-1) K(-1) at T = 2.2 K for 3 and -ΔSm = 27.1 J kg(-1) K(-1) at T = 2.4 K for 4, both for an applied field change of 7 T.

Download full-text PDF

Source
http://dx.doi.org/10.1002/chem.201501992DOI Listing

Publication Analysis

Top Keywords

decanuclear ln10
8
smm behavior
8
ln5 complexes
8
ln10 wheels
4
wheels vertex-shared
4
vertex-shared spirocyclic
4
spirocyclic ln5
4
ln5 cores
4
cores synthesis
4
synthesis structure
4

Similar Publications

The reaction of a Schiff base ligand (LH3) with lanthanide salts, pivalic acid and triethylamine in 1:1:1:3 and 4:5:8:20 stoichiometric ratios results in the formation of decanuclear Ln10 (Ln = Dy (1), Tb (2), and Gd (3)) and pentanuclear Ln5 complexes (Ln = Gd (4), Tb (5), and Dy (6)), respectively. The formation of Ln10 and Ln5 complexes are fully governed by the stoichiometry of the reagents used. Detailed magnetic studies on these complexes (1-6) have been carried out.

View Article and Find Full Text PDF

Pillared-layer cluster organic frameworks constructed from nanoscale Ln10 and Cu16 clusters.

Inorg Chem

June 2014

State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 West Yangqiao Road, Fuzhou, Fujian 350002, China.

Two pillared-layer cluster organic frameworks, [Ln5(μ3-OH)4(μ-H2O)Cu8I8L11]·H2O (L = 4-pyridin-4-yl-benzoate; Ln = Dy(1), Eu(2)), have been made by employing lanthanide oxide and copper(I) halide as the source of lanthanide and transitional metal under hydrothermal condition. Compared to the pillared-layer frameworks constructed from heterometallic layers and organic pillars, these two compounds are derived from lanthanide cluster organic layers and copper(I) halide cluster motifs. Thus, there are two distinct types of inorganic metal connectors in the structure, one is hydroxo lanthanide [Ln10(μ3-OH)8](22+) (Ln10) cluster, and the other is copper(I) halide [Cu16I16] (Cu16) cluster.

View Article and Find Full Text PDF

Reactions of Ln(III) acetate (Ln = Pr and Nd) and a polydentate Schiff-base in a mixture of methanol and acetonitrile resulted in the unprecedented assembly of novel Ln(10) aggregates containing two Ln(5) pentagons templated by mu(5)-CO(3)(2-), introduced via spontaneous fixation of atmospheric carbon dioxide. Magnetic analysis using an expression including the ligand field effects and molecular field approximation indicates weak antiferromagnetic coupling between the metal ions. This synthetic approach may represent a promising new route toward the design of new lanthanide clusters and novel multifunctional materials.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!