Molecular and Electronic Structures and Single-Molecule Magnet Behavior of Tris(thioether)–Iron Complexes Containing Redox-Active α-Diimine Ligands

The mononuclear single-molecule magnet (SMM) [Dy(tta)3(L)]⋅C6H14 (1) (where tta− = 2-thenoyltrifluoroacetonate and L = 4,5-bis(propylthio)-tetrathiafulvalene-2-(2-pyridyl)benzimidazole-methyl-2-pyridine) was studied by spectro-electrochemistry. The resulting electronic spectra of the three oxidation states 1, 1+∙, and 12+ were rationalized by time-dependent density functional theory (TD-DFT) calculations starting from the DFT optimized structures. The modulation of the magnetic anisotropy of the DyIII center upon oxidation was also inspected at the Complete Active Space Self-Consistent Field (CASSCF) level of calculation.

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Electroswitching of the single-molecule magnet behaviour in an octahedral spin crossover cobalt(ii) complex with a redox-active pyridinediimine ligand

Chemical Communications ◽

10.1039/d0cc03357j ◽

2020 ◽

Vol 56 (81) ◽

pp. 12242-12245

Author(s):

Renato Rabelo ◽

Luminita Toma ◽

Nicolás Moliner ◽

Miguel Julve ◽

Francesc Lloret ◽

...

Keyword(s):

Single Molecule ◽

Spin Crossover ◽

Single Molecule Magnet ◽

Redox Active

A unique example of electroswitchable spin crossover molecular nanomagnet which proceeds through one-electron oxidation of the slow-relaxing paramagnetic low-spin CoII ion (SCo = 1/2, ON) to the diamagnetic low-spin CoIII ion (SCo = 0, OFF).

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A redox-active luminescent ytterbium based single molecule magnet

Chemical Communications ◽

10.1039/c2cc37635k ◽

2013 ◽

Vol 49 (6) ◽

pp. 615-617 ◽

Cited By ~ 149

Author(s):

Fabrice Pointillart ◽

Boris Le Guennic ◽

Stéphane Golhen ◽

Olivier Cador ◽

Olivier Maury ◽

...

Keyword(s):

Single Molecule ◽

Single Molecule Magnet ◽

Redox Active

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Field-Induced Dysprosium Single-Molecule Magnet Based on a Redox-Active Fused 1,10-Phenanthroline-Tetrathiafulvalene-1,10-Phenanthroline Bridging Triad

Frontiers in Chemistry ◽

10.3389/fchem.2018.00552 ◽

2018 ◽

Vol 6 ◽

Cited By ~ 4

Author(s):

Bertrand Lefeuvre ◽

Olivier Galangau ◽

Jessica Flores Gonzalez ◽

Vincent Montigaud ◽

Vincent Dorcet ◽

...

Keyword(s):

Single Molecule ◽

Single Molecule Magnet ◽

Redox Active

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Insights into Single-Molecule-Magnet Behavior from the Experimental Electron Density of Linear Two-Coordinate Iron Complexes

Inorganic Chemistry ◽

10.1021/acs.inorgchem.8b03301 ◽

2019 ◽

Vol 58 (5) ◽

pp. 3211-3218 ◽

Cited By ~ 11

Author(s):

Maja K. Thomsen ◽

Andreas Nyvang ◽

James P. S. Walsh ◽

Philip C. Bunting ◽

Jeffrey R. Long ◽

...

Keyword(s):

Electron Density ◽

Single Molecule ◽

Iron Complexes ◽

Single Molecule Magnet ◽

Experimental Electron Density

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Chiral or Luminescent Lanthanide Single-Molecule Magnets Involving Bridging Redox Active Triad Ligand

Inorganics ◽

10.3390/inorganics9070050 ◽

2021 ◽

Vol 9 (7) ◽

pp. 50

Author(s):

Bertrand Lefeuvre ◽

Jessica Flores Gonzalez ◽

Carlo Andrea Mattei ◽

Vincent Dorcet ◽

Olivier Cador ◽

...

Keyword(s):

Magnetic Field ◽

Single Molecule ◽

Applied Magnetic Field ◽

Near Infrared ◽

Dinuclear Complexes ◽

Single Molecule Magnets ◽

Single Molecule Magnet ◽

X Ray ◽

Redox Active ◽

Raman Process

The reactions between the bis(1,10-phenantro[5,6-b])tetrathiafulvalene triad (L) and the metallo-precursors Yb(hfac)3(H2O)2 (hfac− = 1,1,1,5,5,5-hexafluoroacetylacetonato anion) and Dy(facam)3 (facam− = 3-trifluoro-acetyl-(+)-camphorato anion) lead to the formation of two dinuclear complexes of formula [Yb2(hfac)6(L)]·2(C7H16) ((1)·2(C7H16)) and [Dy2((+)facam)6(L)]·2(C6H14) ((2)·2(C6H14)). The X-ray structures reveal that the L triad bridges two terminal Yb(hfac)3 or Dy(facam)3 units. (1)·2(C7H16) behaved as a near infrared YbIII centered emitter and a field-induced Single-Molecule Magnet (SMM) while (2)·2(C6H14) displayed SMM behavior in both zero- and in-dc field. The magnetization mainly relaxes through a Raman process for both complexes under an optimal applied magnetic field.

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Exchange-Biasing in a Dinuclear Dysprosium(III) Single-Molecule Magnet with a Large Energy Barrier for Magnetization Reversal

10.26434/chemrxiv.10260494 ◽

2019 ◽

Author(s):

Tian Han ◽

Marcus J. Giansiracusa ◽

Zi-Han Li ◽

You-Song Ding ◽

Nicholas F. Chilton ◽

...

Keyword(s):

Single Molecule ◽

Magnetization Reversal ◽

Energy Barrier ◽

Magnetic Hysteresis ◽

Large Energy ◽

Magnetic Studies ◽

Bridging Ligands ◽

Single Molecule Magnet ◽

Exchange Biasing

A dichlorido-bridged dinuclear dysprosium(III) single-molecule magnet [Dy2L2(µ-Cl)2(THF)2] has been made using a diamine-bis(phenolate) ligand, H2L. Magnetic studies show an energy barrier for magnetization reversal (Ueff) around 1000 K. Exchange-biasing effect is clearly seen in magnetic hysteresis with steps up to 4 K. Ab initio calculations exclude the possibility of pure dipolar origin of this effect leading to the conclusion that super-exchange via the chloride bridging ligands is important.

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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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