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Carter AB, Zhang N, Kühne IA, Keene TD, Powell AK, Kitchen JA. Layered Ln(III) Complexes from a Sulfonate-Based 1,8-Naphthalimide: Structures, Magnetism and Photophysics. ChemistrySelect 2019. [DOI: 10.1002/slct.201900152] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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52
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Perfetti M, Rinck J, Cucinotta G, Anson CE, Gong X, Ungur L, Chibotaru L, Boulon ME, Powell AK, Sessoli R. Single Crystal Investigations Unravel the Magnetic Anisotropy of the "Square-In Square" Cr 4Dy 4 SMM Coordination Cluster. Front Chem 2019; 7:6. [PMID: 30733942 PMCID: PMC6353784 DOI: 10.3389/fchem.2019.00006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 01/07/2019] [Indexed: 01/15/2023] Open
Abstract
In the search for new single molecule magnets (SMM), i.e., molecular systems that can retain their magnetization without the need to apply an external magnetic field, a successful strategy is to associate 3d and 4f ions to form molecular coordination clusters. In order to efficiently design such systems, it is necessary to chemically project both the magnetic building blocks and the resultant interaction before the synthesis. Lanthanide ions can provide the required easy axis magnetic anisotropy that hampers magnetization reversal. In the rare examples of 3d/4f SMMs containing CrIII ions, the latter turn out to act as quasi-isotropic anchors which can also interact via 3d-4f coupling to neighbouring Ln centres. This has been demonstrated in cases where the intramolecular exchange interactions mediated by CrIII ions effectively reduce the efficiency of tunnelling without applied magnetic field. However, describing such high nuclearity systems remains challenging, from both experimental and theoretical perspectives, because the overall behaviour of the molecular cluster is heavily affected by the orientation of the individual anisotropy axes. These are in general non-collinear to each other. In this article, we combine single crystal SQUID and torque magnetometry studies of the octanuclear [Cr4Dy4(μ3-OH)4(μ-N3)4(mdea)4(piv)8]·3CH2Cl2 single molecule magnet (piv=pivalate and mdea=N-methyldiethanol amine). These experiments allowed us to probe the magnetic anisotropy of this complex which displays slow magnetization dynamics due to the peculiar arrangement of the easy-axis anisotropy on the Dy sites. New ab initio calculations considering the entire cluster are in agreement with our experimental results.
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Scherthan L, Schmidt SFM, Auerbach H, Hochdörffer T, Wolny JA, Bi W, Zhao J, Hu MY, Toellner T, Alp EE, Brown DE, Anson CE, Powell AK, Schünemann V. 161
Dy Time‐Domain Synchrotron Mössbauer Spectroscopy for Investigating Single‐Molecule Magnets Incorporating Dy Ions. Angew Chem Int Ed Engl 2019; 58:3444-3449. [DOI: 10.1002/anie.201810505] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 11/23/2018] [Indexed: 11/07/2022]
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54
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Peewasan K, Merkel MP, Zarschler K, Stephan H, Anson CE, Powell AK. Tetranuclear Cu(ii)-chiral complexes: synthesis, characterization and biological activity. RSC Adv 2019; 9:24087-24091. [PMID: 35527904 PMCID: PMC9069531 DOI: 10.1039/c9ra03586a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 07/19/2019] [Indexed: 01/16/2023] Open
Abstract
A pair of tetranuclear chiral Cu(ii)-Schiff-base complexes were synthesized using enantiomerically pure (S)-H2L and (R)-H2L ligands. These were characterised using single-crystal X-ray diffraction and CD spectroscopy and their biological activity tested.
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Vieru V, Ungur L, Cemortan V, Sukhanov A, Baniodeh A, Anson CE, Powell AK, Voronkova V, Chibotaru LF. Magnetization Blocking in Fe2
III
Dy2
III
Molecular Magnets: Ab Initio Calculations and EPR Spectroscopy. Chemistry 2018; 24:16652-16661. [DOI: 10.1002/chem.201803821] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Indexed: 11/11/2022]
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56
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He M, Chen X, Bodenstein T, Nyvang A, Schmidt SFM, Peng Y, Moreno-Pineda E, Ruben M, Fink K, Gamer MT, Powell AK, Roesky PW. Enantiopure Benzamidinate/Cyclooctatetraene Complexes of the Rare-Earth Elements: Synthesis, Structure, and Magnetism. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00412] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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57
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Balinski K, Schneider L, Wöllermann J, Buling A, Joly L, Piamonteze C, Feltham HLC, Brooker S, Powell AK, Delley B, Kuepper K. Element specific determination of the magnetic properties of two macrocyclic tetranuclear 3d-4f complexes with a Cu 3Tb core by means of X-ray magnetic circular dichroism (XMCD). Phys Chem Chem Phys 2018; 20:21286-21293. [PMID: 29922775 DOI: 10.1039/c7cp08689j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We apply X-ray magnetic circular dichroism to study the internal magnetic structure of two very promising star shaped macrocyclic complexes with a CuII3TbIII core. These complexes are rare examples prepared with a macrocyclic ligand that show indications of SMM (Single Molecule Magnet) behavior, and they differ only in ring size: one has a propylene linked macrocycle, [CuII3TbIII(LPr)(NO3)2(MeOH)(H2O)2](NO3)·3H2O (nickname: Cu3Tb(LPr)), and the other has the butylene linked analogue, [CuII3TbIII(LBu)(NO3)2(MeOH)(H2O)](NO3)·3H2O (nickname: Cu3Tb(LBu)). We analyze the orbital and spin contributions to the Cu and Tb ions quantitatively by applying the spin and orbital sum rules concerning the L2 (M4)/L3 (M5) edges. In combination with appropriate ligand field simulations, we demonstrate that the Tb(iii) ions contribute with high orbital magnetic moments to the magnetic anisotropy, whereas the ligand field determines the easy axis of magnetization. Furthermore, we confirm that the Cu(ii) ions in both molecules are in a divalent valence state, the magnetic moments of the three Cu ions appear to be canted due to 3d-3d intramolecular magnetic interactions. For Cu3Tb(LPr), the corresponding element specific magnetization loops reflect that the Cu(ii) contribution to the overall magnetic picture becomes more important as the temperature is lowered. This implies a low value for the 3d-4f coupling.
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58
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Feltham HLC, Clérac R, Peng Y, Moreno-Pineda E, Powell AK, Brooker S. The Effect of Modifying the Macrocyclic Ring Size on Zn3Ln(Ln= Dy, Er, and Yb) Single-Molecule Magnet Behavior. Z Anorg Allg Chem 2018. [DOI: 10.1002/zaac.201800155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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59
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Peng Y, Anson CE, Powell AK. Cover Feature: A W-Shaped Ga-Dy-Dy-Dy-Ga Cluster: Synthesis, Characterization, and Magnetic Properties (ChemPlusChem 7/2018). Chempluschem 2018. [DOI: 10.1002/cplu.201800266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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60
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Peng Y, Anson CE, Powell AK. A W-Shaped Ga-Dy-Dy-Dy-Ga Cluster: Synthesis, Characterization, and Magnetic Properties. Chempluschem 2018; 83:676-681. [PMID: 31950630 DOI: 10.1002/cplu.201800049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/22/2018] [Indexed: 11/09/2022]
Abstract
A W-shaped {Ga-Dy-Dy-Dy-Ga} coordination cluster, [Ga2 Dy3 (L)6 (MeO)2 (MeOH)3 ]⋅NO3 ⋅7 MeOH (1) with H2 L, (E)-2-(2-hydroxy-3-methoxy-benzylideneamino)phenol was synthesized, characterized, and the magnetic properties investigated. The magnetic measurements indicate that the compound shows single-molecule magnet (SMM) behavior under zero dc field. This suggests that the combination of GaIII ions and DyIII ions (4 f) is a successful strategy to assemble SMM clusters. The combination of these metal ions also offers prospects in dual functionality therapeutics for medical applications.
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61
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Peng Y, Mereacre V, Anson CE, Powell AK. Butterfly M 2 IIIEr 2 (M III = Fe and Al) SMMs: Synthesis, Characterization, and Magnetic Properties. ACS OMEGA 2018; 3:6360-6368. [PMID: 31458819 PMCID: PMC6644375 DOI: 10.1021/acsomega.8b00550] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 04/27/2018] [Indexed: 06/10/2023]
Abstract
The reaction of N-(2-pyridylmethyl)iminodiethanol (H2L, pmide), FeCl2·4H2O or AlCl3·6H2O with ErCl3·6H2O and p-Me-PhCO2H in the ratio of 2:1:1:4 in the presence of Et3N in MeOH and MeCN yielded compounds [Fe2Er2(μ3-OH)2(pmide)2(p-Me-PhCO2)6]·2MeCN (1) and [Al2Er2(μ3-OH)2(pmide)2(p-Me-PhCO2)6]·2MeCN (2). These two complexes are isostructural, possessing a planar butterfly motif with the ErIII ions in the wingtip positions. Both compounds show single molecule magnet (SMM) behavior. For the [Al2Er2] compound, the slow relaxation of the magnetization under zero applied direct current (dc) field does not show maxima, but the relaxation processes could be analyzed using an applied dc field of 1000 Oe. In-depth alternating current measurements under different dc fields on the [Fe2Er2] compound reveals that the Fe-Fe and Fe-Er interactions speed up the relaxation and decrease the energy barrier height of the SMM in comparison with the [Al2Er2] case.
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62
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Rusbridge EK, Peng Y, Powell AK, Robinson D, Fitzpatrick AJ. An octahedral tetrachlorido Fe(ii) complex with aminopyrazinium ligands from a serendipitous redox synthesis exhibiting magnetic exchange through non-covalent 3-D architectures. Dalton Trans 2018; 47:7644-7648. [PMID: 29796507 DOI: 10.1039/c8dt01401a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An air stable, neutral Fe(ii) complex with four equatorial chlorido ligands has been stabilised through a serendipitous redox process and in situ ligand protonation. A three-dimensional non-covalent network composed of halogen bonding and π-π stacking promotes magnetic exchange interactions though the lattice. The electronic structure has been investigated using DFT.
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63
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Zhang X, Liu S, Vieru V, Xu N, Gao C, Wang BW, Shi W, Chibotaru LF, Gao S, Cheng P, Powell AK. Frontispiece: Coupling Influences SMM Properties for Pure 4 f Systems. Chemistry 2018. [DOI: 10.1002/chem.201882364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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64
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Zhang X, Liu S, Vieru V, Xu N, Gao C, Wang BW, Shi W, Chibotaru LF, Gao S, Cheng P, Powell AK. Coupling Influences SMM Properties for Pure 4 f Systems. Chemistry 2018; 24:6079-6086. [DOI: 10.1002/chem.201705350] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Indexed: 02/03/2023]
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65
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Ibrahim M, Moreno-Pineda E, Bergfeldt T, Anson CE, Powell AK. Synthesis and Characterization of a Heterometallic Extended Architecture Based on a Manganese(II)-Substituted Sandwich-Type Polyoxotungstate. MATERIALS 2018; 11:ma11010155. [PMID: 29342122 PMCID: PMC5793653 DOI: 10.3390/ma11010155] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 01/11/2018] [Accepted: 01/13/2018] [Indexed: 11/16/2022]
Abstract
The reaction of [α-P2W15O56]12− with MnII and DyIII in an aqueous basic solution led to the isolation of an all inorganic heterometallic aggregate Na10(OH2)42[{Dy(H2O)6}2Mn4P4W30O112(H2O)2]·17H2O (Dy2Mn4-P2W15). Single-crystal X-ray diffraction revealed that Dy2Mn4-P2W15 crystallizes in the triclinic system with space group P1¯, and consists of a tetranuclear manganese(II)-substituted sandwich-type phosphotungstate [Mn4(H2O)2(P2W15O56)2]16− (Mn4-P2W15), Na, and DyIII cations. Compound Dy2Mn4-P2W15 exhibits a 1D ladder-like chain structure based on sandwich-type segments and dysprosium cations as linkers, which are further connected into a three-dimensional open framework by sodium cations. The title compound was structurally and compositionally characterized in solid state by single-crystal XRD, powder X-ray diffraction (PXRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric (TGA), and elemental analyses. Further, the absorption and emission electronic spectra in aqueous solutions of Dy2Mn4-P2W15 and Mn4-P2W15 were studied. Also, magnetic properties were studied and compared with the magnetic behavior of [Mn4(H2O)2(P2W15O56)2]16−.
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66
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Akhtar MN, Lan Y, AlDamen MA, Zheng YZ, Anson CE, Powell AK. Effect of ligand substitution on the SMM properties of three isostructural families of double-cubane Mn4Ln2 coordination clusters. Dalton Trans 2018; 47:3485-3495. [DOI: 10.1039/c7dt04304j] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Three isostructural Mn–Ln families consists of 22 complexes have been presented. Only 7, 15, and 22 for Tb, 8 and 16 for Dy, and 20 for Sm displayed slow magnetization relaxation.
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67
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Kumar P, Griffiths K, Anson CE, Powell AK, Kostakis GE. A tetranuclear CuII2DyIII2 coordination cluster as a Suzuki (C–C) coupling reaction promoter. Dalton Trans 2018; 47:17202-17205. [DOI: 10.1039/c8dt04371j] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The air stable and high yielding tetranuclear coordination cluster [CuII2DyIII2L4(NO3)2(CH3CN)2]·2(CH3CN) promotes the Suzuki coupling reaction of phenylboronic acid with substituted aryl halides under environmentally benign conditions.
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68
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Abouelwafa AS, Hauser A, Mereacre V, Lan Y, Long GJ, Grandjean F, Buth G, Anson CE, Powell AK. Search for Electron Delocalization from [Fe(CN)6]3– to the Dication of Viologen in (DNP)3[Fe(CN)6]2·10H2O. Inorg Chem 2017; 56:6477-6488. [DOI: 10.1021/acs.inorgchem.7b00540] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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69
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Peng Y, Mereacre V, Anson CE, Zhang Y, Bodenstein T, Fink K, Powell AK. Field-Induced Co(II) Single-Ion Magnets with mer-Directing Ligands but Ambiguous Coordination Geometry. Inorg Chem 2017; 56:6056-6066. [PMID: 28485955 DOI: 10.1021/acs.inorgchem.6b02743] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three air-stable Co(II) mononuclear complexes with different aromatic substituents have been prepared and structurally characterized by single-crystal X-ray diffraction. The mononuclear complexes [Co(H2L1)2]·2THF (1), [Co(HL2)2] (2), and [Co(H2L3)2]·CH2Cl2 (3) (where H3L1, H2L2, and H3L3 represent 3-hydroxy-naphthalene-2-carboxylic acid (6-hydroxymethyl-pyridin-2-ylmethylene) hydrazide, nicotinic acid (6-hydroxymethyl-pyridin-2-ylmethylene) hydrazide, and 2-hydroxy-benzoic acid (6-hydroxymethyl-pyridin-2-ylmethylene) hydrazide, respectively) feature a distorted mer octahedral coordination geometry. Detailed magnetic studies of 1-3 have been conducted using direct and alternating current magnetic susceptibility data. Field-induced slow magnetic relaxation was observed for these three complexes. There are few examples of such behavior in (distorted) octahedral coordination geometry (OC) Co(II) mononuclear complexes with uniaxial anisotropy. Analysis of the six-coordinate Co(II) mononuclear single-ion magnets (SIMs) in the literature using the SHAPE program revealed that they all show what is best described as distorted trigonal prismatic (TRP) coordination geometry, and in general, these show negative D zero-field splitting (ZFS) values. On the other hand, all the Co(II) mononuclear complexes displaying what is best approximated as distorted octahedral (OC) coordination geometry show positive D values. In the new Co(II) mononuclear complexes we describe here, there is an ambiguity, since the rigid tridentate ligands confer what is best described for an octahedral complex as a mer coordination geometry, but the actual shape of the first coordination sphere is between octahedral and trigonal prismatic. The negative D values observed experimentally and supported by high-level electronic structure calculations are thus in line with a trigonal prismatic geometry. However, a consideration of the rhombicity as indicated by the E value of the ZFS in conjunction with the SHAPE analysis shows that in this case it is difficult to distinguish between the OC and TRP descriptions.
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70
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Schmidt SFM, Koo C, Mereacre V, Park J, Heermann DW, Kataev V, Anson CE, Prodius D, Novitchi G, Klingeler R, Powell AK. A Three-Pronged Attack To Investigate the Electronic Structure of a Family of Ferromagnetic Fe 4Ln 2 Cyclic Coordination Clusters: A Combined Magnetic Susceptibility, High-Field/High-Frequency Electron Paramagnetic Resonance, and 57Fe Mössbauer Study. Inorg Chem 2017; 56:4796-4806. [PMID: 28186414 DOI: 10.1021/acs.inorgchem.6b02682] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present the synthesis, structure, magnetic properties, as well as the Mössbauer and electron paramagnetic resonance studies of a ring-shaped [FeIII4LnIII2(Htea)4(μ-N3)4(N3)3(piv)3] (Ln = Y 1, Gd 2, Tb 3, Dy 4, Ho 5, Er, 6) coordination cluster. The Dy, Tb, and Ho analogues show blocking of the magnetization at low temperatures without applied fields. The anisotropy of the 3d ion and the exchange interaction between 3d and 4f ions in Fe4Ln2 complexes are unambiguously determined by high-field/high-frequency electron paramagnetic resonance measurements at low temperature. Ferromagnetic exchange interaction JFe-Ln is found which decreases upon variation of the Ln ions to larger atomic numbers. This dependence is similar to the behavior shown in the effective barrier values of complexes 3-5. Further information about the anisotropy of the Ln3+ ions was gathered with 57Fe Mössbauer spectroscopy, and the combination of these methods provides detailed information regarding the electronic structure of these complexes.
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71
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Jin HG, Jiang X, Kühne IA, Clair S, Monnier V, Chendo C, Novitchi G, Powell AK, Kadish KM, Balaban TS. Microwave-Mediated Synthesis of Bulky Lanthanide Porphyrin-Phthalocyanine Triple-Deckers: Electrochemical and Magnetic Properties. Inorg Chem 2017; 56:4864-4873. [PMID: 28406618 DOI: 10.1021/acs.inorgchem.6b03056] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Five heteroleptic lanthanide porphyrin-bis-phthalocyanine triple-decker complexes with bulky peripheral groups were prepared via microwave-assisted synthesis and characterized in terms of their spectroscopic, electrochemical, and magnetic properties. These compounds, which were easily obtained under our preparative conditions, would normally not be accessible in large quantities using conventional synthetic methods, as a result of the low yield resulting from steric congestion of bulky groups on the periphery of the phthalocyanine and porphyrin ligands. The electrochemically investigated triple-decker derivatives undergo four reversible one-electron oxidations and three reversible one-electron reductions. The sites of oxidation and reduction were assigned on the basis of redox potentials and UV-vis spectral changes during electron-transfer processes monitored by thin-layer spectroelectrochemistry, in conjunction with assignments of electronic absorption bands of the neutral compounds. Magnetic susceptibility measurements on two derivatives containing TbIII and DyIII metal ions reveal the presence of ferromagnetic interactions, probably resulting from magnetic dipolar interactions. The TbIII derivative shows SMM behavior under an applied field of 0.1 T, where the direct and Orbach process can be determined, resulting in an energy barrier of Ueff = 132.0 K. However, Cole-Cole plots reveal the presence of two relaxation processes, the second of which takes place at higher frequencies, with the data conforming to a 1/t ∝ T7 relation, thus suggesting that it can be assigned to a Raman process. Attempts were made to form two-dimensional (2D) self-assembled networks on a highly oriented pyrolytic graphite (HOPG) surface but were unsuccessful due to bulky peripheral groups on the two Pc macrocycles.
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72
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Leblanc N, Genovese D, De Cola L, Powell AK. A platform with connections in many directions - further remarkable facets to the multifaceted methylbiquinoxen dication. Phys Chem Chem Phys 2017; 19:6981-6988. [PMID: 27929154 DOI: 10.1039/c6cp07538j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The N,N'-dimethyl-3,3'-biquinoxalinium "methylbiquinoxen" dicationic platform is revealed to have even more fascinating possibilities than we originally thought in terms of its chemical versatility. In addition to its rich redox chemistry and coordination abilities, we have now unveiled an unexpected Lewis acid/base chemistry linked with a tuneable switching of its luminescence properties. This, amongst other things, allows for the facile fluorescent covalent labelling of hydroxyl-terminated materials. This platform provides intriguing chemical prospects realised in molecular systems such as porphyrins as well as an easy alternative functionalisation methodology to that provided by click-chemistry.
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73
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Schmidt SFM, Merkel MP, Kostakis GE, Buth G, Anson CE, Powell AK. SMM behaviour and magnetocaloric effect in heterometallic 3d–4f coordination clusters with high azide : metal ratios. Dalton Trans 2017; 46:15661-15665. [DOI: 10.1039/c7dt03149a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present the synthesis and characterization of heterometallic compounds with a very large azide to metal ratio and fascinating magnetic properties.
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74
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Leblanc N, Sproules S, Powell AK. An alternative method to access diverse N,N′-diquaternised-3,3′-biquinoxalinium “biquinoxen” dications. NEW J CHEM 2017. [DOI: 10.1039/c7nj00531h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Biquinoxens synthesis via oxidative radical homocoupling of N-alkylquinoxalinium – an alternative method.
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75
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Chen S, Mereacre V, Kostakis GE, Anson CE, Powell AK. Systematic studies of hexanuclear {MIII4LnIII2} complexes (M = Fe, Ga; Ln = Er, Ho): structures, magnetic properties and SMM behavior. Inorg Chem Front 2017. [DOI: 10.1039/c7qi00091j] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first heterometallic GaIII–ErIII single-molecule magnet has been synthesized and the role of GaIII in extracting the FeIII–ErIII and ErIII–ErIII interaction has been assessed.
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