Counterintuitive Single-Molecule Magnet Behaviour in Two Polymorphs of One-Dimensional Compounds Involving Chiral BINOL-Derived Bisphosphate Ligands

The coordination reaction of the [Dy(hfac)3(H2O)2] units (hfac− = 1,1,1,5,5,5-hexafluoroacetylacetonate) with the [8′-(Diphenoxylphosphinyl)[1,1′-binaphthalen]-8-yl]diphenoxylphosphine oxide ligand (L) followed by a crystallisation in a 1:3 CH2Cl2:n-hexane solvent mixture led to the isolation of a new polymorph of formula [(Dy(hfac)3((S)-L))3]n (1). The X-ray structure on single crystal of 1 revealed the formation of a mono-dimensional coordination polymer with three crystallographically independent DyIII centres, which crystallised in the polar chiral P21 space group. Ac magnetic measurements highlighted single-molecule magnet behaviour under both zero and 1000 Oe applied magnetic field with magnetic relaxation through quantum tunneling of the magnetisation (QTM, zero field only) and Raman processes. Despite the three crystallographically independent DyIII centres adopting a distorted D4d coordination environment, a single slow magnetic relaxation contribution was observed at a slower rate than its previously studied [(Dy(hfac)3((S)-L))]n (2) polymorph.

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Zero-field slow magnetic relaxation in a uranium(iii) complex with a radical ligand

Chemical Communications ◽

10.1039/c4cc04486j ◽

2014 ◽

Vol 50 (71) ◽

pp. 10262-10264 ◽

Cited By ~ 21

Author(s):

Joana T. Coutinho ◽

Maria A. Antunes ◽

Laura C. J. Pereira ◽

Joaquim Marçalo ◽

Manuel Almeida

Keyword(s):

Single Molecule ◽

Magnetic Relaxation ◽

Zero Field ◽

Single Molecule Magnet ◽

Slow Magnetic Relaxation ◽

Bipyridine Ligand ◽

Radical Ligand

Single-molecule-magnet behaviour in [U(TpMe2)2(bipy˙)], a U(iii) complex with a radical bipyridine ligand, having magnetic contributions from both the metal and the ligand.

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Zero-field slow magnetic relaxation from single Co(ii) ion: a transition metal single-molecule magnet with high anisotropy barrier

Chemical Science ◽

10.1039/c3sc21893g ◽

2013 ◽

Vol 4 (4) ◽

pp. 1802 ◽

Cited By ~ 234

Author(s):

Yuan-Yuan Zhu ◽

Chang Cui ◽

Yi-Quan Zhang ◽

Jun-Hua Jia ◽

Xiao Guo ◽

...

Keyword(s):

Transition Metal ◽

Single Molecule ◽

Magnetic Relaxation ◽

Zero Field ◽

Single Molecule Magnet ◽

High Anisotropy ◽

Slow Magnetic Relaxation

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Single molecule magnet behavior observed in a 1-D dysprosium chain with quasi-D5h symmetry

Dalton Transactions ◽

10.1039/c5dt04147c ◽

2015 ◽

Vol 44 (48) ◽

pp. 20834-20838 ◽

Cited By ~ 36

Author(s):

Xing-Cai Huang ◽

Ming Zhang ◽

Dayu Wu ◽

Dong Shao ◽

Xin-Hua Zhao ◽

...

Keyword(s):

Coordination Polymers ◽

Single Molecule ◽

Magnetic Relaxation ◽

Single Molecule Magnet ◽

One Dimensional ◽

Slow Magnetic Relaxation

Two one-dimensional coordination polymers with pentagonal bipyramidal DyIII centres show slow magnetic relaxation featuring single molecule magnet behavior.

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Field-Induced Single-Molecule Magnets of Dysprosium Involving Quinone Derivatives

Magnetochemistry ◽

10.3390/magnetochemistry7020024 ◽

2021 ◽

Vol 7 (2) ◽

pp. 24

Author(s):

Konstantin Martyanov ◽

Jessica Flores Gonzalez ◽

Sergey Norkov ◽

Bertrand Lefeuvre ◽

Vincent Dorcet ◽

...

Keyword(s):

Hydrogen Bonds ◽

Single Molecule ◽

Magnetic Relaxation ◽

Magnetic Measurements ◽

Single Molecule Magnets ◽

Single Molecule Magnet ◽

X Ray ◽

Tert Butyl ◽

Raman Process ◽

Coordination Reaction

The coordination reaction of the [Dy(hfac)3(H2O)2] units (hfac− = 1,1,1,5,5,5-hexafluoroacetylacetonate) with the two quinone-based derivatives 4,7-di-tert-butyl-2-(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-ylidene)benzo[d][1,3]dithiole-5,6-dione (L1) and 7,8-dithiabicyclo[4.2.0]octa-1,5-diene-3,4-dione,2,5bis(1,1-dimethylethyl) (L2) led respectively to the complexes [Dy(hfac)3(H2O)(L1)] (1) and [Dy(hfac)3(H2O) (L2)]⋅(C6H14)(CH2Cl2) (2)⋅(C6H14)(CH2Cl2). X-ray structures on single crystal of 1 and 2⋅(C6H14)(CH2Cl2) revealed the coordination of the DyIII on the bischelating oxygenated quinone site and the formation of dimeric species through hydrogen bonds. Ac magnetic measurements highlighted field-induced single-molecule magnet behavior with magnetic relaxation through a Raman process.

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Slow magnetic relaxation in dinuclear dysprosium and holmium phenoxide bridged complexes: a Dy2 single molecule magnet with a high energy barrier

Inorganic Chemistry Frontiers ◽

10.1039/d1qi00152c ◽

2021 ◽

Author(s):

Matilde Fondo ◽

Julio Corredoira-Vázquez ◽

Ana M. Garcia-Deibe ◽

Jesus Sanmartin Matalobos ◽

Silvia Gómez-Coca ◽

...

Keyword(s):

Crystal Structures ◽

Single Molecule ◽

Energy Barrier ◽

Magnetic Relaxation ◽

High Energy ◽

Single Molecule Magnet ◽

High Energy Barrier ◽

Slow Magnetic Relaxation

Dinuclear [M(H3L1,2,4)]2 (M = Dy, Dy2; M = Ho, Ho2) complexes were isolated from an heptadentate aminophenol ligand. The crystal structures of Dy2·2THF, and the pyridine adducts Dy2·2Py and Ho2·2Py,...

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A Dy(III) Fluorescent Single-Molecule Magnet Based on a Rhodamine 6G Ligand

Inorganics ◽

10.3390/inorganics9070051 ◽

2021 ◽

Vol 9 (7) ◽

pp. 51

Author(s):

Lin Miao ◽

Mei-Jiao Liu ◽

Man-Man Ding ◽

Yi-Quan Zhang ◽

Hui-Zhong Kou

Keyword(s):

Magnetic Properties ◽

Single Molecule ◽

Magnetic Relaxation ◽

Rhodamine 6G ◽

Bond Angle ◽

Magnetic Measurements ◽

Single Molecule Magnet ◽

Lanthanide Metals ◽

Process Studies ◽

Dual Functions

The complexes of lanthanide metals, especially dysprosium, can generally exhibit excellent magnetic properties. By means of modifying ligands, dual functions or even multi-functions can be achieved. Here, we synthesized an eight-coordinate Dy(III) complex 1, [Dy(HL-o)2(MeOH)2](ClO4)3·4.5MeOH, which is single-molecule magnet (SMM), and the introduction of the rhodamine 6G chromophore in the ring-opened ligand HL-o realizes ligand-centered fluorescence in addition to SMM. Magnetic measurements and ab initio calculations indicate that the magnetic relaxation for complex 1 should be due to the Raman relaxation process. Studies on magneto-structural correlationship of the rhodamine salicylaldehyde hydrazone Dy(III) complexes show that the calculated energy of the first Kramers Doublet (EKD1) is basically related to the Ophenoxy-Dy-Ophenoxy bond angle, i.e., the larger Ophenoxy-Dy-Ophenoxy bond angle corresponds to a larger EKD1.

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Polyoxometalate-Supported Lanthanoid Single-Molecule Magnets

Australian Journal of Chemistry ◽

10.1071/ch14166 ◽

2014 ◽

Vol 67 (11) ◽

pp. 1542 ◽

Cited By ~ 24

Author(s):

Michele Vonci ◽

Colette Boskovic

Keyword(s):

Single Molecule ◽

Energy Barrier ◽

Magnetic Relaxation ◽

Donor Ligands ◽

Single Molecule Magnets ◽

Single Molecule Magnet ◽

Coordination Numbers ◽

Oxygen Donor ◽

Slow Magnetic Relaxation

Polyoxometalates are robust and versatile multidentate oxygen-donor ligands, eminently suitable for coordination to trivalent lanthanoid ions. To date, 10 very different structural families of such complexes have been found to exhibit slow magnetic relaxation due to single-molecule magnet (SMM) behaviour associated with the lanthanoid ions. These families encompass complexes with between one and four of the later lanthanoid ions: Tb, Dy, Ho, Er, and Yb. The lanthanoid coordination numbers vary between six and eleven and a range of coordination geometries are evident. The highest energy barrier to magnetisation reversal measured to date for a lanthanoid–polyoxometalate SMM is Ueff/kB = 73 K for the heterodinuclear Dy–Eu compound (Bu4N)8H4[DyEu(OH)2(γ-SiW10O36)2].

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Structures, fluorescence properties and magnetic properties of a series of rhombus-shaped LnIII4 clusters: magnetocaloric effect and single-molecule-magnet behavior

New Journal of Chemistry ◽

10.1039/c9nj02872b ◽

2019 ◽

Vol 43 (33) ◽

pp. 12941-12949 ◽

Cited By ~ 19

Author(s):

Wen-Min Wang ◽

Li Zhang ◽

Xian-Zhen Li ◽

Li-Yuan He ◽

Xin-Xin Wang ◽

...

Keyword(s):

Magnetic Properties ◽

Magnetocaloric Effect ◽

Single Molecule ◽

Magnetic Relaxation ◽

Magnetic Refrigeration ◽

Fluorescence Properties ◽

Relaxation Processes ◽

Magnetic Studies ◽

Single Molecule Magnet ◽

Slow Magnetic Relaxation

A family LnIII4 clusters were successfully synthesized and structurally characterized. Magnetic studies show that Gd4 cluster displays magnetic refrigeration, while Dy4 cluster demonstrates two distinct slow magnetic relaxation processes.

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