Predictable self-assembled [2 × 2] Ln(iii)4 square grids (Ln = Dy,Tb)—SMM behaviour in a new lanthanide cluster motif

Anwar, Muhammad U.; Thompson, Laurence K.; Habib, Fatemah; Murugesu, Muralee

doi:10.1039/c2cc17546k

Cited by 154 publications

(72 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…16,18 To date, extensive research attempts have been performed to probe how the exchange coupling affects SMM properties in lanthanide-based complexes, thus yielding a series of ground-breaking results, such as the high blocking temperature discovered in N 2 3− -bridged Tb 2 complex and sulfur-bridged organometallic dysprosium complexes. 7,12 Herein, to investigate the effects of magnetic interaction and coordination geometry on the SMM behavior in Dy-based compounds with hula hoop-like geometry, we employed two ligands with different features, H 3 ■ EXPERIMENTAL SECTION General Information. All chemicals were used as received without any further purification, and all manipulations were performed under aerobic conditions.…”

Section: ■ Introductionmentioning

confidence: 99%

“…) was dissolved in a mixed solvent of CH3 OH/ CH 3 CN (5 mL/10 mL) followed by the addition of Dy(NO 3 ) 3 ·6H 2 O (0.1 mmol) and triethylamine (0.2 mmol), which gave a clear red solution after stirring for 3 h. This solution was left unperturbed to allow the slow evaporation of the solvent. After 4 days, red blockshaped crystals were formed in 38% yield (23 mg).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Modulating Magnetic Dynamics of Dy₂ System through the Coordination Geometry and Magnetic Interaction

et al. 2013

View full text Add to dashboard Cite

Two new dinuclear dysprosium compounds, [Dy 2 (HL 1 ) 2 (PhCOO) 2 (CH 3 OH) 2 ] (1) and [Dy 2 (L 2 ) 2 (NO 3 ) 2 -(CH 3 OH) 2 ]·2CH 3 OH·4H 2 O (2), have been assembled through applying two ligands with different coordination pockets. The different features of ligands H 3 L 1 and H 2 L 2 result in the distinct coordination geometry of the metal ions in their respective structures. The Dy ions of complexes 1 and 2 were linked by the alkoxide-and hydrazone-O, and display the hula hoop-like and the broken hula hoop-like coordination geometry, respectively. Consequently, these two compounds show distinct magnetic properties. Complex 1 behaves as a single molecule magnet (SMM) with rather slow quantum tunneling rate (τ > 274 ms), while no SMM behavior was observed for complex 2. In addition, the comparison of the structural parameters among the similar Dy 2 SMMs with hula hoop-like geometry reveals the significant role played by coordination geometry and magnetic interaction in modulating the relaxation dynamics of SMMs. ■ INTRODUCTIONSince the seminal discovery of single molecule magnet (SMM) behavior in a Mn 12 complex during the 1990s, the study of SMM has been the focus of chemistry, physics, and materials science, where the quantum world of magnetization for single molecule clusters meets the bulk scale of classical physics. 1−4 The continued interest stems from their prospects of applications in information storage and quantum computing. 5 In particular, recent years have seen a flurry of results for lanthanide-based SMMs, including the highest relaxation energy barriers for multinuclear clusters 6 and the highest blocking temperature, 7 which mainly benefit from the significant magnetic anisotropy of lanthanide ions arising from the large, unquenched orbital angular momentum. 8,9 Remarkably, the alteration of coordination geometry on local metal sites and/or magnetic interaction between them turns out to be a key factor in modulating the relaxation dynamics of lanthanide-based SMMs. 10−13 The high axial coordination geometry around Dy III ions is an important feature enabling lanthanide complexes functioning as SMMs with high barrier, such as the approximate D 4d symmetry in [LnPc 2 ] 14,15 and the axial hula hoop-like geometry in asymmetric Dy 2 16 and Dy 6 triangular prism. 17 In addition, the tune of magnetic interactions can also bring about some surprising results, although exchange coupling between lanthanide metal centers is very weak. 16,18 To date, extensive research attempts have been performed to probe how the exchange coupling affects SMM properties in lanthanide-based complexes, thus yielding a series of ground-breaking results, such as the high blocking temperature discovered in N 2 3− -bridged Tb 2 complex and sulfur-bridged organometallic dysprosium complexes. 7,12 Herein, to investigate the effects of magnetic interaction and coordination geometry on the SMM behavior in Dy-based compounds with hula hoop-like geometry, we employed two ligands with different features, H 3 L 1 19−21 and H 2 L 2 ...

show abstract

Section: ■ Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

Modulating Magnetic Dynamics of Dy₂ System through the Coordination Geometry and Magnetic Interaction

et al. 2013

View full text Add to dashboard Cite

show abstract

“…5.31. In 2012, two similar Dy 4 square grids were constructed firstly with some important differences being the absence or presence of the central μ 4 -O atom and the bridging atoms at each side [35]. In the Dy 4 grid in Fig.…”

Section: Hydrazone Ligands From Bis-acylhydrazidementioning

confidence: 99%

Hydrazone-Based Lanthanide Single-Molecule Magnets

Tang

Zhang

2015

Lanthanide Single Molecule Magnets

View full text Add to dashboard Cite

To date, a great number of lanthanide SMMs have been reported through applying rigid mixed-donor hydrazone ligands which can be modified very easily by altering the hydrazide or aldehyde parts. This chapter first focuses on two typical polynuclear Dy complexes which greatly contribute to the elucidation of two-step relaxation model and are subsequently devoted to the constructions of lanthanide SMMs based on the different hydrazide parts and their magnetic analysis. Therefore, the assembly of hydrazone ligands with lanthanide salts under different conditions turns out to be an effective way to discover new lanthanide SMMs and to explore the origin of complicated magnetic dynamics.Keywords Hydrazone ligands · Two-step relaxation · Keto-enol tautomerism · Hula hoop · Magnetic exchange As seen in the third and fourth chapters, Schiff base ligands exhibit some advantages over other ligands in the assembly of polynuclear lanthanide SMMs. Generally speaking, such ligands incorporate a great number of coordinating donors such as N and O atoms with an affinity for lanthanide ions, thus leading to the polytopic coordination within a single ligand. More importantly, such donors are usually coupled into multiple dentate coordination pockets preferring chelating a single lanthanide center, which is favorable to self-assembly of lanthanide clusters. As a special class in Schiff base ligands, hydrazone ligands exhibit not only the common features of Schiff base ligands but also some special coordination characteristics, which have proven to be beneficial to achieve high-performance lanthanide SMMs. Therefore, considerable lanthanide SMMs have been obtained using hydrazone ligands which seem to be in great abundance and variety due to the various alternations of hydrazide and aldehyde reagents, as seen in Fig. 5.1.

show abstract

“…Modelling the data according to the Arrhenius equation results in U eff values of 28.7 and 69.3 K and τ 0 of 6.3 × 10 −5 and 5.9 × 10 −8 s, below and above 6 K respectively. 55 45 A few examples include [Mn III 6 O 2 (Etsao) 6 (O 2 CPh(Me) 2 ) 2 (EtOH) 6 ] (Et-saoH 2 = 2-hydroxyphenylpropanone oxime) (28) 46 (c) Schiff bases.…”

Section: A Choice Of Ligandsmentioning

confidence: 99%

Nanoscopic molecular magnets

Goswami

Mondal

Konar

2015

Inorg. Chem. Front.

View full text Add to dashboard Cite

Nanoscopic molecular magnets have attracted tremendous interest in recent years both from an experimental and a theoretical point of view because of their potential application in magnetic data storage devices, quantum computing and molecular spintronics. These molecules have crucial advantages over magnetic nanoparticles in terms of their perfectly mono-dispersed phase, chemical flexibility and high purity. This review discusses a few basic concepts that are needed to understand the magnetic properties observed in nanoscopic molecular magnets, a chemical approach for their synthesis and magnetostructural correlations. It includes a few selected examples and discusses the new trends in the field.

show abstract

Predictable self-assembled [2 × 2] Ln(iii)4 square grids (Ln = Dy,Tb)—SMM behaviour in a new lanthanide cluster motif

Cited by 154 publications

References 20 publications

Modulating Magnetic Dynamics of Dy₂ System through the Coordination Geometry and Magnetic Interaction

Modulating Magnetic Dynamics of Dy₂ System through the Coordination Geometry and Magnetic Interaction

Hydrazone-Based Lanthanide Single-Molecule Magnets

Nanoscopic molecular magnets

Contact Info

Product

Resources

About

Predictable self-assembled [2 × 2] Ln(iii)4 square grids (Ln = Dy,Tb)—SMM behaviour in a new lanthanide cluster motif

Cited by 154 publications

References 20 publications

Modulating Magnetic Dynamics of Dy2 System through the Coordination Geometry and Magnetic Interaction

Modulating Magnetic Dynamics of Dy2 System through the Coordination Geometry and Magnetic Interaction

Hydrazone-Based Lanthanide Single-Molecule Magnets

Nanoscopic molecular magnets

Contact Info

Product

Resources

About

Modulating Magnetic Dynamics of Dy₂ System through the Coordination Geometry and Magnetic Interaction

Modulating Magnetic Dynamics of Dy₂ System through the Coordination Geometry and Magnetic Interaction