Elongation of magnetic relaxation times in a single-molecule magnet through intermetallic interactions: a clamshell-type dinuclear terbium(iii)-phthalocynaninato quadruple-decker complex

Clamshell-type terbium(iii)-phthalocyaninato quadruple-decker complex was synthesized. Magnetic measurements revealed that Tb–Tb interactions caused an increase in the magnetic relaxation time.

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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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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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[2 + 2] Photochemical modulation of the Dy(iii) single-molecule magnet: opposite influence on the energy barrier and relaxation time

Inorganic Chemistry Frontiers ◽

10.1039/c7qi00221a ◽

2017 ◽

Vol 4 (8) ◽

pp. 1311-1318 ◽

Cited By ~ 22

Author(s):

Long-Fei Wang ◽

Jiang-Zhen Qiu ◽

Yan-Cong Chen ◽

Jun-Liang Liu ◽

Quan-Wen Li ◽

...

Keyword(s):

Relaxation Time ◽

Uv Irradiation ◽

Single Molecule ◽

Low Temperatures ◽

Energy Barrier ◽

Magnetic Relaxation ◽

Single Molecule Magnet ◽

Raman Process

The photochemical [2 + 2] reaction on a mononuclear Dy(iii) single-molecule magnet leads to the higher energy barrier after UV irradiation, along with the shorter magnetic relaxation time that is due to the acceleration of Raman process at low temperatures.

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

Magnetochemistry ◽

10.3390/magnetochemistry7110150 ◽

2021 ◽

Vol 7 (11) ◽

pp. 150

Author(s):

Carlo Andrea Mattei ◽

Bertrand Lefeuvre ◽

Vincent Dorcet ◽

Gilles Argouarch ◽

Olivier Cador ◽

...

Keyword(s):

Single Molecule ◽

Magnetic Relaxation ◽

Magnetic Measurements ◽

Solvent Mixture ◽

Zero Field ◽

Coordination Environment ◽

Single Molecule Magnet ◽

One Dimensional ◽

Slow Magnetic Relaxation ◽

Coordination Reaction

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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Correlating Blocking Temperatures in Single Molecule Magnets with Raman Relaxation

10.26434/chemrxiv.7067669 ◽

2018 ◽

Author(s):

Marcus J. Giansiracusa ◽

Andreas Kostopoulos ◽

George F. S. Whitehead ◽

David Collison ◽

Floriana Tuna ◽

...

Keyword(s):

Relaxation Time ◽

Single Molecule ◽

Energy Barrier ◽

Thermal Relaxation ◽

Relaxation Mechanism ◽

Blocking Temperature ◽

Single Molecule Magnets ◽

Single Molecule Magnet ◽

Key Parameter

We report a six coordinate DyIII single-molecule magnet (SMM) with an energy barrier of 1110 K for thermal relaxation of magnetization. The sample shows no retention of magnetization even at 2 K and this led us to find a good correlation between the blocking temperature and the Raman relaxation regime for SMMs. The key parameter is the relaxation time (𝜏switch) at the point where the Raman relaxation mechanism becomes more important than Orbach.

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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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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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Regulation of magnetic relaxation behavior by replacing 3d transition metal ions in [M2Dy2] complexes containing two different organic chelating ligands

Dalton Transactions ◽

10.1039/c9dt00774a ◽

2019 ◽

Vol 48 (27) ◽

pp. 10011-10022 ◽

Cited By ~ 10

Author(s):

Hui-Sheng Wang ◽

Cheng-Ling Yin ◽

Zhao-Bo Hu ◽

Yong Chen ◽

Zhi-Quan Pan ◽

...

Keyword(s):

Transition Metal ◽

Metal Ions ◽

Single Molecule ◽

Magnetic Relaxation ◽

Transition Metal Ions ◽

Relaxation Behavior ◽

Organic Ligands ◽

Chelating Ligands ◽

Single Molecule Magnet

Two [MIII2DyIII2] complexes (M = Fe for 1 and Co for 2) with mixed organic ligands were obtained. Complex 2 exhibits single molecule magnet behavior with Ueff = 64.0(9) K.

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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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