Dysprosium Single-Molecule Magnets Involving 1,10-Phenantroline-5,6-dione Ligand

The two mononuclear complexes of the formula [Dy(tta)3(L)] (1) and [Dy(hfac)3(L)] (2) (where tta- = 2-thenoytrifluoroacetylacetonate and hfac- = 1,1,1,5,5,5-hexafluoroacetylacetonate) were obtained from the coordination reaction of the Dy(tta)3·2H2O or Dy(hfac)3·2H2O units with the 1,10-phenantroline-5,6-dione ligand (L). Their structures have been determined by X-ray diffraction studies on single crystals, and they revealed a supramolecular assembly of tetramers through σ-π interactions. Both complexes displayed a Single-Molecule Magnet (SMM) behavior without an external applied magnetic field. Magnetic relaxation happened through Orbach, Raman and Quantum Tunneling of the Magnetization (QTM). Wavefunction theory calculations were realized to rationalize the magnetic properties.

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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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Simple Method and Materials to Target Co(II)-Dy(III) Multi-Nuclear Magnetic Compounds and Single Molecule Magnets (SMMs): Synthesis, Structure, and Magnetic Studies

Australian Journal of Chemistry ◽

10.1071/ch12336 ◽

2013 ◽

Vol 66 (1) ◽

pp. 75 ◽

Cited By ~ 14

Author(s):

Yan Zhu ◽

Feng Luo ◽

Xue-Feng Feng ◽

Zhen-Wei Liao ◽

Yu-Mei Song ◽

...

Keyword(s):

Single Molecule ◽

Donor Ligands ◽

X Ray Diffraction ◽

Magnetic Studies ◽

Single Molecule Magnets ◽

Simple Method ◽

Single Molecule Magnet ◽

X Ray ◽

Nitrobenzoic Acid ◽

Slow Magnetic Relaxation

In this work, based on mixed N-, O-donor ligands, a series of Co(ii)-Dy(iii) compounds are synthesised and characterised by single crystal X-ray diffraction and magnetic studies. These compounds include Co2(phen)2Dy(PhCOO)7 (1), Co2(phen)2Dy2(PhCOO)10 (2), Co(bpy)Dy(H2O)(CH3-PhCOO)5 (3), Co(phen)Dy(H2O)(CH3-PhCOO)5 (4), Co2(phen)2Dy(NO2-PhCOO)7 (5), Co2(phen)2Dy2(NO2-PhCOO)10 (6), and Co2(bpy)2Dy2(NO2-PhCOO)10 (7), where phen, bpy, CH3-PhCOOH, and NO2-PhCOOH are 1,10-phenanthroline, 2,2′-bipyridine, 3-methylbenzoic acid, and 3-nitrobenzoic acid, respectively. In these cases, di-, tri-, and tetranuclear Co-Dy clusters are observed. Direct current (DC) magnetic susceptibility reveals ferromagnetic or antiferromagnetic behaviour, whilst dynamic magnetic studies disclose single molecule magnet (SMM)-like slow magnetic relaxation for most of these compounds.

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Cobalt(II) chloride adducts with acetonitrile, propan-2-ol and tetrahydrofuran: considerations on nuclearity, reactivity and synthetic applications

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229617000705 ◽

2017 ◽

Vol 73 (2) ◽

pp. 104-114 ◽

Cited By ~ 1

Author(s):

Danilo Stinghen ◽

André Luis Rüdiger ◽

Siddhartha O. K. Giese ◽

Giovana G. Nunes ◽

Jaísa F. Soares ◽

...

Keyword(s):

Single Molecule ◽

Building Blocks ◽

Direct Reaction ◽

X Ray Diffraction ◽

Single Molecule Magnets ◽

X Ray ◽

Ft Ir ◽

Bond Network ◽

Solvent Molecules ◽

Intramolecular Hydrogen

High-spin cobalt(II) complexes are considered useful building blocks for the synthesis of single-molecule magnets (SMM) because of their intrinsic magnetic anisotropy. In this work, three new cobalt(II) chloride adducts with labile ligands have been synthesized from anhydrous CoCl2, to be subsequently employed as starting materials for heterobimetallic compounds. The products were characterized by elemental, spectroscopic (EPR and FT–IR) and single-crystal X-ray diffraction analyses.trans-Tetrakis(acetonitrile-κN)bis(tetrahydrofuran-κO)cobalt(II) bis[(acetonitrile-κN)trichloridocobaltate(II)], [Co(C2H3N)4(C4H8O)2][CoCl3(C2H3N)]2, (1), comprises mononuclear ions and contains both acetonitrile and tetrahydrofuran (thf) ligands, The coordination polymercatena-poly[[tetrakis(propan-2-ol-κO)cobalt(II)]-μ-chlorido-[dichloridocobalt(II)]-μ-chlorido], [Co2Cl4(C3H8O)4], (2′), was prepared by direct reaction between anhydrous CoCl2and propan-2-ol in an attempt to rationalize the formation of the CoCl2–alcohol adduct (2), probably CoCl2(HOiPr)m. The binuclear complex di-μ-chlorido-1:2κ4Cl:Cl-dichlorido-2κ2Cl-tetrakis(tetrahydrofuran-1κO)dicobalt(II), [Co2Cl4(C4H8O)4], (3), was obtained from (2) after recrystallization from tetrahydrofuran. All three products present cobalt(II) centres in both octahedral and tetrahedral environments, the former usually less distorted than the latter, regardless of the nature of the neutral ligand. Product (2′) is stabilized by an intramolecular hydrogen-bond network that appears to favour atransarrangement of the chloride ligands in the octahedral moiety; this differs from thecisdisposition found in (3). The expected easy displacement of the bound solvent molecules from the metal coordination sphere makes the three compounds good candidates for suitable starting materials in a number of synthetic applications.

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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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An air stable radical-bridged dysprosium single molecule magnet and its neutral counterpart: redox switching of magnetic relaxation dynamics

Chemical Communications ◽

10.1039/c6cc09824j ◽

2017 ◽

Vol 53 (14) ◽

pp. 2283-2286 ◽

Cited By ~ 50

Author(s):

Brian S. Dolinar ◽

Silvia Gómez-Coca ◽

Dimitris I. Alexandropoulos ◽

Kim R. Dunbar

Keyword(s):

Magnetic Properties ◽

Single Molecule ◽

Quantum Tunneling ◽

Magnetic Relaxation ◽

Thermal Relaxation ◽

Relaxation Dynamics ◽

Single Molecule Magnet ◽

Neutral Compound ◽

Redox Switching ◽

P Addition

Addition of a radical to the bridging tetrazine ligand of a Dy2 complex dramatically alters the magnetic properties. The radical complex undergoes magnetic relaxation via a thermal relaxation pathway, whereas the neutral compound relaxes via quantum tunneling of the magnetization.

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Determination of d-Orbital Populations in a Cobalt(II) Single-Molecule Magnet Using Single-Crystal X-ray Diffraction

Inorganic Chemistry ◽

10.1021/acs.inorgchem.8b00513 ◽

2018 ◽

Vol 57 (12) ◽

pp. 6913-6920 ◽

Cited By ~ 11

Author(s):

Matthew Craven ◽

Mathilde H. Nygaard ◽

Joseph M. Zadrozny ◽

Jeffrey R. Long ◽

Jacob Overgaard

Keyword(s):

Single Crystal ◽

Single Molecule ◽

X Ray Diffraction ◽

Single Molecule Magnet ◽

X Ray

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Chiral and kryptoracemic Dy(iii) complexes with field-induced single molecule magnet behavior

CrystEngComm ◽

10.1039/c8ce01052h ◽

2018 ◽

Vol 20 (32) ◽

pp. 4582-4589 ◽

Cited By ~ 3

Author(s):

Ying-Ying Zhang ◽

Jing-Tao Yu ◽

Bo Li ◽

De-Jing Li ◽

Zhi-Gang Gu ◽

...

Keyword(s):

Single Molecule ◽

Magnetic Relaxation ◽

Single Molecule Magnets ◽

Single Molecule Magnet

Crystalline mode modulation and magnetic relaxation manipulation can be realized by the introduction of different anions into mononuclear Dy(iii) single molecule magnets (SMMs).

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Series of Chloranilate-Bridged Dinuclear Lanthanide Complexes: Kramers Systems Showing Field-Induced Slow Magnetic Relaxation

Magnetochemistry ◽

10.3390/magnetochemistry5020030 ◽

2019 ◽

Vol 5 (2) ◽

pp. 30 ◽

Cited By ~ 3

Author(s):

Ryuta Ishikawa ◽

Shoichi Michiwaki ◽

Takeshi Noda ◽

Keiichi Katoh ◽

Masahiro Yamashita ◽

...

Keyword(s):

Magnetic Susceptibility ◽

Single Molecule ◽

Magnetic Relaxation ◽

Lanthanide Complexes ◽

Relaxation Processes ◽

X Ray Diffraction ◽

Single Molecule Magnets ◽

Magnetic Susceptibility Data ◽

Susceptibility Data ◽

Slow Magnetic Relaxation

A series of chloralilate-bridged dinuclear lanthanide complexes of formula [{LnIII(Tp)2}2(μ-Cl2An)]·2CH2Cl2, where Cl2An2− and Tp− represent the chloranilate and hydrotris (pyrazolyl)borate ligands, respectively, and Ln = Gd (1), Tb (2), Ho (3), Er (4), and Yb (5) was synthesized. All five complexes were characterized by an elemental analysis, infrared spectroscopy, single crystal X-ray diffraction, and SQUID measurements. The complexes 1–5 in the series were all isostructural. A comparison of the temperature dependence of the dc magnetic susceptibility data of these complexes revealed clear differences depending on the lanthanide center. Ac magnetic susceptibility measurements revealed that none of the five complexes exhibited a slow magnetic relaxation under a zero applied dc field. On the other hand, the Kramers systems (complexes 4 and 5) clearly displayed a slow magnetic relaxation under applied dc fields, suggesting field-induced single-molecule magnets that occur through Orbach and Raman relaxation processes.

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Redox Modulation of Field-Induced Tetrathiafulvalene-Based Single-Molecule Magnets of Dysprosium

Magnetochemistry ◽

10.3390/magnetochemistry6030034 ◽

2020 ◽

Vol 6 (3) ◽

pp. 34

Author(s):

Siham Tiaouinine ◽

Jessica Flores Gonzalez ◽

Vincent Montigaud ◽

Carlo Andrea Mattei ◽

Vincent Dorcet ◽

...

Keyword(s):

Magnetic Properties ◽

Single Molecule ◽

Chemical Oxidation ◽

Dinuclear Complexes ◽

Computational Results ◽

Single Molecule Magnets ◽

Redox Modulation ◽

Single Molecule Magnet ◽

Tert Butyl ◽

Coordination Reaction

The complexes [Dy2(tta)6(H2SQ)] (Dy-H2SQ) and [Dy2(tta)6(Q)]·2CH2Cl2 (Dy-Q) (tta− = 2-thenoyltrifluoroacetonate) were obtained from the coordination reaction of the Dy(tta)3·2H2O units with the 2,2′-benzene-1,4-diylbis(6-hydroxy-4,7-di-tert-butyl-1,3-benzodithiol-2-ylium-5-olate ligand (H2SQ) and its oxidized form 2,2′-cyclohexa-2,5-diene-1,4-diylidenebis(4,7-di-tert-butyl-1,3-benzodithiole-5,6-dione (Q). The chemical oxidation of H2SQ in Q induced an increase in the coordination number from 7 to 8 around the DyIII ions and by consequence a modulation of the field-induced Single-Molecule Magnet behavior. Computational results rationalized the magnetic properties of each of the dinuclear complexes.

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