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Petrecca M, Albino M, Tredici IG, Anselmi-Tamburini U, Passaponti M, Caneschi A, Sangregorio C. High Density Nanostructured Soft Ferrites Prepared by High Pressure Field Assisted Sintering Technique. J Nanosci Nanotechnol 2019; 19:4974-4979. [PMID: 30913809 DOI: 10.1166/jnn.2019.16791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The synthesis of highly compacted, nanostructured soft magnets is highly desirable due to their promising properties for the development of electronic devices working at frequency higher than 2 MHz. In this work we investigated the potentiality of High Pressure Field Assisted Sintering Technique (HP-FAST). To this aim, we first synthesized soft Mn-Zn ferrite magnetic nanoparticles (MNPs) through an easy-scalable, eco-friendly strategy based on aqueous co-precipitation in basic media, starting from transition metal chlorides. Powder X-ray diffraction (PXRD) and Transmission Electron Microscopy (TEM) analyses evidenced the formation of crystalline nanoparticles with the cubic spinel structure and average crystal size of 7.5 nm. Standard magnetometric measurements showed a saturation magnetization value of ca. 56 emu/g and no magnetic irreversibility at room temperature. The MNPs were then compacted applying an uniaxial pressure over a toroidal shaped die. In order to obtain a material with a density close to the bulk one, the as-prepared green toroids underwent either a classic sintering treatment, obtaining a microstructured system, or to High Pressure Field Assisted Sintering Technique (HP-FAST), which allowed for preserving the nanostructure. The relative permeability and core losses of the toroidal samples were evaluated in the frequency range 1-2 MHz using an in-house built setup. The comparison of the behavior of samples obtained by the two different sintering approaches showed the nanostructured samples had a much smaller relative magnetic permeability (ten times lower than the microstructured sample) and, consequently, higher core losses. However, when samples with similar μr were compared, a significant decrease of core losses at the larger frequencies was observed. This result suggests HP-FAST is a very promising approach to prepare high density nanostructured soft magnetic materials.
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Affiliation(s)
- M Petrecca
- Dip. di Chimica, "Ugo Schiff", Università degli Studi di Firenze, via della Lastruccia 3-13, I-50019 Sesto Fiorentino, and Consorzio INSTM, Italy
| | - M Albino
- Dip. di Chimica, "Ugo Schiff", Università degli Studi di Firenze, via della Lastruccia 3-13, I-50019 Sesto Fiorentino, and Consorzio INSTM, Italy
| | - I G Tredici
- Dip. di Chimica, Università degli Studi di Pavia, v.le Taramelli 12, I-27100 Pavia, Italy
| | - U Anselmi-Tamburini
- Dip. di Chimica, Università degli Studi di Pavia, v.le Taramelli 12, I-27100 Pavia, Italy
| | - M Passaponti
- Dip. di Chimica, "Ugo Schiff", Università degli Studi di Firenze, via della Lastruccia 3-13, I-50019 Sesto Fiorentino, and Consorzio INSTM, Italy
| | - A Caneschi
- Dip. di Chimica, "Ugo Schiff", Università degli Studi di Firenze, via della Lastruccia 3-13, I-50019 Sesto Fiorentino, and Consorzio INSTM, Italy
| | - C Sangregorio
- Dip. di Chimica, "Ugo Schiff", Università degli Studi di Firenze, via della Lastruccia 3-13, I-50019 Sesto Fiorentino, and Consorzio INSTM, Italy
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Corsi I, Winther-Nielsen M, Sethi R, Punta C, Della Torre C, Libralato G, Lofrano G, Sabatini L, Aiello M, Fiordi L, Cinuzzi F, Caneschi A, Pellegrini D, Buttino I. Ecofriendly nanotechnologies and nanomaterials for environmental applications: Key issue and consensus recommendations for sustainable and ecosafe nanoremediation. Ecotoxicol Environ Saf 2018; 154:237-244. [PMID: 29476973 DOI: 10.1016/j.ecoenv.2018.02.037] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 02/02/2018] [Accepted: 02/12/2018] [Indexed: 05/23/2023]
Abstract
The use of engineered nanomaterials (ENMs) for environmental remediation, known as nanoremediation, represents a challenging and innovative solution, ensuring a quick and efficient removal of pollutants from contaminated sites. Although the growing interest in nanotechnological solutions for pollution remediation, with significant economic investment worldwide, environmental and human risk assessment associated with the use of ENMs is still a matter of debate and nanoremediation is seen yet as an emerging technology. Innovative nanotechnologies applied to water and soil remediation suffer for a proper environmental impact scenario which is limiting the development of specific regulatory measures and the exploitation at European level. The present paper summarizes the findings from the workshop: "Ecofriendly Nanotechnology: state of the art, future perspectives and ecotoxicological evaluation of nanoremediation applied to contaminated sediments and soils" convened during the Biannual ECOtoxicology Meeting 2016 (BECOME) held in Livorno (Italy). Several topics have been discussed and, starting from current state of the art of nanoremediation, which represents a breakthrough in pollution control, the following recommendations have been proposed: (i) ecosafety has to be a priority feature of ENMs intended for nanoremediation; ii) predictive safety assessment of ENMs for environmental remediation is mandatory; (iii) greener, sustainable and innovative nano-structured materials should be further supported; (iii) those ENMs that meet the highest standards of environmental safety will support industrial competitiveness, innovation and sustainability. The workshop aims to favour environmental safety and industrial competitiveness by providing tools and modus operandi for the valorization of public and private investments.
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Affiliation(s)
- I Corsi
- Department of Physical, Earth and Environmental Sciences, University of Siena, via Mattioli, 4-53100 Siena, Italy.
| | - M Winther-Nielsen
- Department of Environment and Toxicology, DHI, Agern Allé 5, 2970 Hoersholm, Denmark
| | - R Sethi
- Department of Environment, Land and Infrastructure Engineering (DIATI), Politecnico di Torino, Italy
| | - C Punta
- Department of Chemistry, Materials, and Chemical Engineering "G. Natta", Politecnico di Milano and RU INSTM, Via Mancinelli 7, 20131 Milano, Italy
| | - C Della Torre
- Department of Bioscience, University of Milano, via Celoria 26, 20133 Milano, Italy
| | - G Libralato
- Department of Biology, University of Naples Federico II, via Cinthia ed. 7, 80126 Naples, Italy
| | - G Lofrano
- Department of Chemical and Biology "A. Zambelli", University of Salerno, via Giovanni Paolo II 132, 84084 Fisciano, SA, Italy
| | - L Sabatini
- Regional Technological District for Advanced Materials, c/o ASEV SpA (management entity), via delle Fiascaie 12, 50053 Empoli, FI, Italy
| | - M Aiello
- Acque Industriali SRL, Via Molise, 1, 56025 Pontedera, PI, Italy
| | - L Fiordi
- Acque Industriali SRL, Via Molise, 1, 56025 Pontedera, PI, Italy
| | - F Cinuzzi
- LABROMARE SRL, Via dell'Artigianato 69, 57121 Livorno, Italy
| | - A Caneschi
- Department of Chemistry & RU INSTM at the University of Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - D Pellegrini
- Institute for Environmental Protection and Research (ISPRA), Piazzale dei marmi 12, 57013 Livorno, Italy
| | - I Buttino
- Institute for Environmental Protection and Research (ISPRA), Piazzale dei marmi 12, 57013 Livorno, Italy.
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Caneschi A, Casu MB. Substrate-induced effects in thin films of a potential magnet composed of metal-free organic radicals deposited on Si(111). Chem Commun (Camb) 2015; 50:13510-3. [PMID: 25238430 DOI: 10.1039/c4cc05990e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We deposit a paramagnetic pyrene derivative of the nitronyl nitroxide radical on Si(111). The molecules experience a strong chemical interaction with the substrate that influences the film growth. We also study the time evolution of the nitronyl nitroxide radical under a micro-focused soft X-ray beam, observing a stable radical as a product. This result hints at the possibility of using this class of materials in dosimeters and sensors.
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Affiliation(s)
- A Caneschi
- Department of Chemistry and RU INSTM, University of Florence, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Italy
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Jung J, Yi X, Huang G, Calvez G, Daiguebonne C, Guillou O, Cador O, Caneschi A, Roisnel T, Le Guennic B, Bernot K. Analysis of the electrostatics in DyIII single-molecule magnets: the case study of Dy(Murex)3. Dalton Trans 2015; 44:18270-5. [DOI: 10.1039/c5dt03345d] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A DyIII-based single-molecule magnet is reported. Ab initio calculations highlight that molecular symmetry plays a predominant role over site symmetry in determining the shape and orientation of DyIII magnetic anisotropy.
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Affiliation(s)
- J. Jung
- UMR 6226 “Institut des Sciences Chimiques de Rennes”
- CNRS–Université de Rennes 1, Campus de Beaulieu
- 35042 Rennes Cedex
- France
| | - X. Yi
- INSA
- UMR CNRS Institut des Sciences Chimiques de Rennes
- 35708 Rennes
- France
| | - G. Huang
- INSA
- UMR CNRS Institut des Sciences Chimiques de Rennes
- 35708 Rennes
- France
| | - G. Calvez
- INSA
- UMR CNRS Institut des Sciences Chimiques de Rennes
- 35708 Rennes
- France
| | - C. Daiguebonne
- INSA
- UMR CNRS Institut des Sciences Chimiques de Rennes
- 35708 Rennes
- France
| | - O. Guillou
- INSA
- UMR CNRS Institut des Sciences Chimiques de Rennes
- 35708 Rennes
- France
| | - O. Cador
- INSA
- UMR CNRS Institut des Sciences Chimiques de Rennes
- 35708 Rennes
- France
| | - A. Caneschi
- La.M.M., INSTM R.U. Firenze and Department of Chemistry
- University of Florence, Via della Lastruccia 3
- I-50019 Sesto Fiorentino
- Italy
| | - T. Roisnel
- UMR 6226 “Institut des Sciences Chimiques de Rennes”
- CNRS–Université de Rennes 1, Campus de Beaulieu
- 35042 Rennes Cedex
- France
| | - B. Le Guennic
- UMR 6226 “Institut des Sciences Chimiques de Rennes”
- CNRS–Université de Rennes 1, Campus de Beaulieu
- 35042 Rennes Cedex
- France
| | - K. Bernot
- INSA
- UMR CNRS Institut des Sciences Chimiques de Rennes
- 35708 Rennes
- France
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Natali Sora I, Caronna T, Fontana F, de Julián Fernández C, Caneschi A, Green M, Bonville P. Charge compensation and magnetic properties in Sr and Cu doped La-Fe perovskites. EPJ Web of Conferences 2013. [DOI: 10.1051/epjconf/20134015005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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de Julián Fernández C, Mattei G, Paz E, Novak RL, Cavigli L, Bogani L, Palomares FJ, Mazzoldi P, Caneschi A. Coupling between magnetic and optical properties of stable Au-Fe solid solution nanoparticles. Nanotechnology 2010; 21:165701. [PMID: 20348591 DOI: 10.1088/0957-4484/21/16/165701] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Au-Fe nanoparticles constitute one of the simplest prototypes of a multifunctional nanomaterial that can exhibit both magnetic and optical (plasmonic) properties. This solid solution, not feasible in the bulk phase diagram in thermal equilibrium, can be formed as a nanostructure by out-of-equilibrium processes. Here, the novel magnetic, optical and magneto-optical properties of ion-implanted Au-Fe solid solution nanoparticles dispersed in a SiO(2) matrix are investigated and correlated. The surface plasmon resonance of the Au-Fe nanoparticles with almost equicomposition is strongly damped when compared to pure Au and to Au-rich Au-Fe nanoparticles. In all cases, the Au atoms are magnetically polarized, as measured by x-ray magnetic circular dichroism, and ferromagnetically coupled with Fe atoms. Although the chemical stability of Au-Fe nanoparticles is larger than that of Fe nanoparticles, both the magnetic moment per Fe atom and the order temperature are smaller. These results suggest that electronic and magnetic properties are more influenced by the hybridization of the electronic bands in the Au-Fe solid solution than by size effects. On the other hand, the magneto-optical transitions allowed in the vis-nIR spectral regions are very similar. In addition, we also observe, after studying the properties of thermally treated samples, that the Au-Fe alloy is stabilized, not by surface effects, but by the combination of the out-of-equilibrium nature of the ion implantation technique and by changes in the properties due to size effects.
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Affiliation(s)
- C de Julián Fernández
- INSTM RU at the Department of Chemistry of the University of Firenze, via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
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Mariani M, Aldrovandi S, Corti M, Lascialfari A, Bogani L, Caneschi A, Sessoli R. Local spin dynamics in doped cobalt(II)-radical magnetic chains studied by 1H NMR. Inorganica Chim Acta 2008. [DOI: 10.1016/j.ica.2008.03.102] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Calvez G, Bernot K, Guillou O, Daiguebonne C, Caneschi A, Mahé N. Sterically-induced synthesis of 3d–4f one-dimensional compounds: A new route towards 3d–4f single chain magnets. Inorganica Chim Acta 2008. [DOI: 10.1016/j.ica.2008.03.040] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Cinti F, Rettori A, Pini MG, Mariani M, Micotti E, Lascialfari A, Papinutto N, Amato A, Caneschi A, Gatteschi D, Affronte M. Two-step magnetic ordering in quasi-one-dimensional helimagnets: possible experimental validation of villain's conjecture about a chiral spin liquid phase. Phys Rev Lett 2008; 100:057203. [PMID: 18352419 DOI: 10.1103/physrevlett.100.057203] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 11/23/2007] [Indexed: 05/26/2023]
Abstract
Low-temperature specific heat, magnetic susceptibility, and zero-field muon spin resonance (microSR) measurements have been performed in the quasi-one-dimensional molecular helimagnetic compound Gd(hfac)3NITEt. The specific heat presents two anomalies at T(0)=2.19+/-0.02 K and T(N)=1.88+/-0.02 K, which both disappear upon the application of a weak magnetic field. Conversely, magnetic susceptibility and muSR data show the divergence of two-spin correlation functions only at T(N)=1.88+/-0.02 K. These results suggest an experimental validation of Villain's conjecture of a two-step magnetic ordering in quasi-one-dimensional XY helimagnets; i.e., the paramagnetic phase and the helical spin solid phase are separated by a chiral spin liquid phase, where translational invariance is broken without violation of rotational invariance.
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Affiliation(s)
- F Cinti
- CNISM and Department of Physics, University of Florence, 50019 Sesto Fiorentino (FI), Italy
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Gillon B, Sangregorio C, Caneschi A, Gatteschi D, Sessoli R, Ressouche E, Pontillon Y. Experimental spin density in the high spin ground state of the Fe8pcl cluster. Inorganica Chim Acta 2007. [DOI: 10.1016/j.ica.2007.01.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Claiser N, Souhassou M, Lecomte C, Gillon B, Carbonera C, Caneschi A, Dei A, Gatteschi D, Bencini A, Pontillon Y, Lelièvre-Berna E. Combined charge and spin density experimental study of the yttrium(III) semiquinonato complex Y(HBPz3)2(DTBSQ) and DFT calculations. J Phys Chem B 2007; 109:2723-32. [PMID: 16851280 DOI: 10.1021/jp0467907] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
High-resolution X-ray diffraction and polarized neutron diffraction experiments have been performed on the Y-semiquinonate complex, Y(HBPz3)2(DTBSQ), in order to determine the charge and spin densities in the paramagnetic ground state, S = (1/2). The aim of these combined studies is to bring new insights to the antiferromagnetic coupling mechanism between the semiquinonate radical and the rare earth ion in the isomorphous Gd(HBPz3)2(DTBSQ) complex. The experimental charge density at 106 K yields detailed information about the bonding between the Y3+ ion and the semiquinonate ligand; the topological charge of the yttrium atom indicates a transfer of about 1.5 electrons from the radical toward the Y3+ ion in the complex, in agreement with DFT calculations. The electron density deformation map reveals well-resolved oxygen lone pairs with one lobe polarized toward the yttrium atom. The determination of the induced spin density at 1.9 K under an applied magnetic field of 9.5 T permits the visualization of the delocalized magnetic orbital of the radical throughout the entire molecule. The spin is mainly distributed on the oxygen atoms [O1 (0.12(1) mu B), O2(0.11(1) mu B)] and the carbon atoms [C21 (0.24(1) mu B), C22(0.20(1) mu B), C24(0.16(1) mu B), C25(0.12(1) mu B)] of the carbonyl ring. A significant spin delocalization on the yttrium site of 0.08(2) mu B is observed, proving that a direct overlap with the radical magnetic orbital can occur at the rare earth site and lead to antiferromagnetic coupling. The DFT calculations are in good quantitative agreement with the experimental charge density results, but they underestimate the spin delocalization of the oxygen toward the yttrium and the carbon atoms of the carbonyl ring.
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Affiliation(s)
- N Claiser
- Laboratoire de Cristallographie et Modélisation des Matériaux Minéraux et Biologiques, UMR CNRS 7036, Université Henri Poincaré-Nancy I, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex, France
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Caneschi A, Gatteschi D, Rey P. The Chemistry and Magnetic Properties of Metal Nitronyl Nitroxide Complexes. Progress in Inorganic Chemistry 2007. [DOI: 10.1002/9780470166406.ch6] [Citation(s) in RCA: 241] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Cinti F, Affronte M, Lascialfari A, Barucci M, Olivieri E, Pasca E, Rettori A, Risegari L, Ventura G, Pini M, Cuccoli A, Roscilde T, Caneschi A, Gatteschi D, Rovai D. Chiral and helical phase transitions in quasi-1D molecular magnets. Polyhedron 2005. [DOI: 10.1016/j.poly.2005.03.124] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Mahé N, Guillou O, Daiguebonne C, Gérault Y, Caneschi A, Sangregorio C, Chane-Ching JY, Car PE, Roisnel T. Polynuclear Lanthanide Hydroxo Complexes: New Chemical Precursors for Coordination Polymers. Inorg Chem 2005; 44:7743-50. [PMID: 16241123 DOI: 10.1021/ic0401086] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis of hexanuclear lanthanide hydroxo complexes by controlled hydrolysis led to polymorphic compounds. The hexanuclear entities crystallize in four different ways that depend on the extent of their hydration. The four structures can be described as hexanuclear lanthanide entities with formula [Ln(6)(mu(6)-O)(mu(3)-OH)(8)(NO(3))(6)(H(2)O)(12)](2+). Two additional NO(3)(-) ions intercalate between the hexanuclear entities in order to ensure the electroneutrality of the crystal structure. Some crystallization water molecules fill the intermolecular space. The three first families of compounds (1-3) exhibit crystal structures that have previously been reported. The fourth family of compounds (4) is described here for the first time. Its chemical formula is [Ln(6)(mu(6)-O)(mu(3)-OH)(8)(NO(3))(6)(H(2)O)(12)](NO(3))(2).2H(2)O (Ln = Gd, Er, and Y). In this paper, the chemical and thermal stabilities of the hexanuclear lanthanide compounds are reported together with the magnetic properties of the Gd(III)-containing species. To use these entities as precursors for new materials, the substitution of the nitrato groups by chloride ions has been studied. Two byproduct compounds have so been obtained: The first (compound 5) is a nitrato/chloride hexanuclear compound of chemical formula [Er(6)(mu(6)-O)(mu(3)-OH)(8)(NO(3))(6)(H(2)O)(12)](NO(3))Cl.2H(2)O. The second one (compound 6) is a polymeric compound in which the hexanuclear entities are linked by an unexpected and original N(2)O(4) bridge. Its chemical formula is [Er(6)(mu(6)-O)(mu(3)-OH)(8)(NO(3))(4)(H(2)O)(11)(OH)(ONONO(2))]Cl(3).2H(2)O. Its crystal structure can be described as the juxtaposition of chainlike molecular motifs. To the best of our knowledge, this is the first example of a coordination polymer synthesized from an isolated polylanthanide hydroxo complex.
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Affiliation(s)
- N Mahé
- Laboratoire de Chimie du Solide et Inorganique Moléculaire, UMR 6511-CNRS-INSA de Rennes, France
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Ienco A, Mealli C, Orlandini A, Galindo A, Grirrane A, del Río D, Pastor A, Fernández Sanz J, Caneschi A. Supramolecular interactions as determining factors of the primary geometry of metallic building blocks. Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305086824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Bogani L, Caneschi A, Fedi M, Gatteschi D, Massi M, Novak MA, Pini MG, Rettori A, Sessoli R, Vindigni A. Finite-size effects in single chain magnets: an experimental and theoretical study. Phys Rev Lett 2004; 92:207204. [PMID: 15169379 DOI: 10.1103/physrevlett.92.207204] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2003] [Indexed: 05/24/2023]
Abstract
The problem of finite-size effects in s=1/2 Ising systems showing slow dynamics of the magnetization is investigated introducing diamagnetic impurities in a Co2+-radical chain. The static magnetic properties have been measured and analyzed considering the peculiarities induced by the ferrimagnetic character of the compound. The dynamic susceptibility shows that an Arrhenius law is observed with the same energy barrier for the pure and the doped compounds while the prefactor decreases, as theoretically predicted. Multiple spin reversal has also been investigated.
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Affiliation(s)
- L Bogani
- Dipartimento di Chimica and INSTM, Università di Firenze, I-50019 Sesto Fiorentino, Italy
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Caneschi A, Gatteschi D, Sangregorio C, Vaz M, Costantino U, Nocchetti M, Vivani R. Intercalation of a nitronyl nitroxide radical into layered inorganic hosts. Inorganica Chim Acta 2002. [DOI: 10.1016/s0020-1693(02)01026-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Caneschi A, Gatteschi D, Hoffman SK, Laugier J, Rey P, Sessoli R. Crystal and molecular structure, magnetic properties and EPR spectra of a trinuclear copper(II) complex with bridging nitronyl nitroxides. Inorg Chem 2002. [DOI: 10.1021/ic00287a002] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Benelli C, Caneschi A, Gatteschi D, Pardi L, Rey P. Structure and magnetic properties of linear-chain complexes of rare-earth ions (gadolinium, europium) with nitronyl nitroxides. Inorg Chem 2002. [DOI: 10.1021/ic00301a024] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Caneschi A, Gatteschi D, Laugier J, Rey P, Sessoli R. Structure and magnetic properties of chains of diamonds of four spins formed by metal(II) hexafluoroacetylacetonates (metal = cobalt, nickel) and the nitronyl nitroxide radical 4,4,5,5-tetramethyl-2-ethyl-4,5-dihydro-1H-imidazolyl-1-oxyl 3-oxide. Inorg Chem 2002. [DOI: 10.1021/ic00282a009] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Caneschi A, Gatteschi D, Laugier J, Pardi L, Rey P, Zanchini C. Structure and magnetic properties of two bis(nitronyl nitroxide) adducts of bis(hexafluoroacetylacetonato) manganese(II). Molecular orbital interpretation of the coupling in manganese-nitroxide complexes. Inorg Chem 2002. [DOI: 10.1021/ic00285a007] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Bencini A, Benelli C, Caneschi A, Carlin RL, Dei A, Gatteschi D. Crystal and molecular structure of and magnetic coupling in two complexes containing gadolinium(III) and copper(II) ions. J Am Chem Soc 2002. [DOI: 10.1021/ja00312a054] [Citation(s) in RCA: 466] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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23
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Caneschi A, Chiesi P, David L, Ferraro F, Gatteschi D, Sessoli R. Crystal structure and magnetic properties of two nitronyl nitroxide biradicals and of their copper(II) complexes. Inorg Chem 2002. [DOI: 10.1021/ic00060a021] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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24
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Caneschi A, Gatteschi D, Sessoli R, Cabello CI, Rey P, Barra AL, Brunel LC. One-dimensional antiferromagnetism in a linear chain containing zinc(II) and a nitronyl nitroxide. Inorg Chem 2002. [DOI: 10.1021/ic00008a038] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Caneschi A, Gatteschi D, Grand A, Laugier J, Pardi L, Rey P. Moderate ferromagnetic exchange between copper(II) and a nitronyl nitroxide in a square-pyramidal adduct. MO interpretation of the mechanism of exchange in copper(II)-nitroxide complexes. Inorg Chem 2002. [DOI: 10.1021/ic00279a019] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Caneschi A, Cornia A, Fabretti AC, Gatteschi D, Malavasi W. Polyiron(III)-Alkoxo Clusters: a Novel Trinuclear Complex and Its Relevance to the Extended Lattices of Iron Oxides and Hydroxides. Inorg Chem 2002. [DOI: 10.1021/ic00122a024] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Bencini A, Benelli C, Caneschi A, Dei A, Gatteschi D. Crystal and molecular structure and magnetic properties of a trinuclear complex containing exchange-coupled GdCu2 species. Inorg Chem 2002. [DOI: 10.1021/ic00224a036] [Citation(s) in RCA: 164] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Caneschi A, Gatteschi D, Laugier J, Rey P, Zanchini C. Synthesis, x-ray crystal structure, and magnetic properties of two dinuclear manganese(II) compounds containing nitronyl nitroxides, imino nitroxides, and their reduced derivatives. Inorg Chem 2002. [DOI: 10.1021/ic00309a040] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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29
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Bencini A, Caneschi A, Dei A, Gatteschi D, Zanchini C, Kahn O. Low-lying electronic energy levels in a series of heterodinuclear complexes containing octahedral nickel(II) and tetrahderal metal(II) (copper, cobalt, and manganese) species. Inorg Chem 2002. [DOI: 10.1021/ic00229a016] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Benelli C, Caneschi A, Gatteschi D, Pardi L, Rey P, Shum DP, Carlin RL. Magnetic properties of lanthanide complexes with nitronyl nitroxides. Inorg Chem 2002. [DOI: 10.1021/ic00301a023] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Caneschi A, Gatteschi D, Renard JP, Rey P, Sessoli R. Magnetic phase transitions in manganese(II) pentafluorobenzoate adducts with nitronyl nitroxides. J Am Chem Soc 2002. [DOI: 10.1021/ja00184a085] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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32
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Brunel LC, Caneschi A, Dei A, Friselli D, Gatteschi D, Hassan AK, Lenci L, Martinelli M, Massa CA, Pardi LA, Popescu F, Ricci I, Sorace L. How and why the characterization of magnetic materials can give directions in the methodological development in high field–high frequency EPR. Res Chem Intermed 2002. [DOI: 10.1163/156856702320267127] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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33
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Caneschi A, Gatteschi D, Lalioti N, Sessoli R, Sorace L, Tangoulis V, Vindigni A. Ising-type magnetic anisotropy in a cobalt(II) nitronyl nitroxide compound: a key to understanding the formation of molecular magnetic nanowires. Chemistry 2002; 8:286-92. [PMID: 11822459 DOI: 10.1002/1521-3765(20020104)8:1<286::aid-chem286>3.0.co;2-d] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The compound [Co(hfac)2-(NITPhOMe)2] (2) (hfac = hexafluoroacetylacetonate, NITPhOMe = 4'-methoxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) crystallizes in the triclinic P1 space group, a= 10.870(5), b = 11.520(5), c = 19.749(5) A, alpha = 78.05(5), beta = 84.20(5), gamma = 64.51(5) degrees, Z = 2. It can be considered a model system for studying the nature of the magnetic anisotropy of [Co(hfac)2(NITPhOMe)] (1), which was recently reported to behave as a molecular magnetic wire. The magnetic anisotropy of 2 was investigated by EPR spectroscopy and SQUID magnetometry both in the polycrystalline powder and in a single crystal. The experimental magnetic anisotropy was related to the anisotropy of the central ion and to the exchange interaction between the cobalt(II) ion and the radicals.
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Affiliation(s)
- A Caneschi
- Dipartimento di Chimica, Università degli Studi di Firenze and INSTM, U.d.R. Firenze, Italy
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Caneschi A, Gatteschi D, Lalioti N, Sessoli R, Sorace L, Tangoulis V, Vindigni A. Ising-Type Magnetic Anisotropy in a Cobalt(II) Nitronyl Nitroxide Compound: A Key to Understanding the Formation of Molecular Magnetic Nanowires. Chemistry 2002. [DOI: 10.1002/1521-3765(20020104)8:1%3c286::aid-chem286%3e3.0.co;2-d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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35
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Armelao L, Bandoli G, Barreca D, Bettinelli M, Bottaro G, Caneschi A. Synthesis and characterization of nanophasic LaCoO3 powders. SURF INTERFACE ANAL 2002. [DOI: 10.1002/sia.1264] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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36
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Lee D, Sorace L, Caneschi A, Lippard SJ. Hydroxo-bridged Cubane-type tetrairon(II) clusters supported by sterically-hindered carboxylate ligands. Inorg Chem 2001; 40:6774-81. [PMID: 11735490 DOI: 10.1021/ic010726b] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of hydroxo-bridged cubane-type tetrairon(II) clusters, [Fe(4)(mu-OH)(4)(mu-O(2)CAr(4)(-)t(BuPh))(2)(mu-OTf)(2)L(4)] (L = C(5)H(5)N (1), 4-(t)BuC(5)H(4)N (2), 3-FC(5)H(4)N (3)), were synthesized by using a sterically hindered carboxylate ligand, 2,6-di(4-tert-butylphenyl)benzoate (Ar(4)(-)t(BuPh)CO(2)(-)). Three different bridging units that mediate weak antiferromagnetic coupling interactions between the metal centers support the unprecedented cubane-type [Fe(4)(mu-OH)(4)](4+) cores in 1-3. The solution structures of 1 and 3 probed by FT-IR and (19)F NMR spectroscopy are consistent with the solid-state geometry determined by X-ray crystallography. Zero-field Mössbauer spectra of 1-3 at 4.2 K are characteristic of high-spin iron(II) centers in nearly identical coordination environments. Compound 1 undergoes two irreversible oxidation processes at ca -10 and +880 mV (vs Fc/Fc(+)), the former approaching quasi-reversible behavior with increased scan rates and a narrow potential sweep range. Comparisons are made with analogous known [Fe(4)X(4)](n)()(+) (X = O, S) units, and the structural integrity of tetrairon fragments upon a change in oxidation state is discussed together with some possible biological implications.
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Affiliation(s)
- D Lee
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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37
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Bodnar SH, Caneschi A, Dei A, Shultz DA, Sorace L. A bis-bidentate dioxolene ligand induces thermal hysteresis in valence tautomerism interconversion processes. Chem Commun (Camb) 2001:2150-1. [PMID: 12240207 DOI: 10.1039/b106192p] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The use of a bis-bidentate ligand in a solid cobalt dioxolene complex affords the necessary cooperative properties that lead to thermal hysteresis in a valence tautomeric interconversion equilibrium.
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Affiliation(s)
- S H Bodnar
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina, USA
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38
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Caneschi A, Dei A, Fabrizi de Biani F, Gütlich P, Ksenofontov V, Levchenko G, Hoefer A, Renz F. Pressure- and temperature-induced valence tautomeric interconversion in a o-dioxolene adduct of a cobalt-tetraazamacrocycle complex. Chemistry 2001; 7:3926-30. [PMID: 11596934 DOI: 10.1002/1521-3765(20010917)7:18<3926::aid-chem3926>3.0.co;2-6] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An electronic switch at the molecular level has been realized by using a class of ionic compounds of the formula [Co(L)(diox)]Y (L = tetraazamacrocyclic ligand, Y = mononegative anion). Such compounds undergo temperature- and pressure-induced intramolecular one-electron transfer equilibria. The transition temperature of interconversion varies with the nature of the counterions Y (Y = PF6, BPh4, I). Surprisingly the effect of the anion on the transition temperature is not only governed by its volume but also by its coulombic interaction.
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Affiliation(s)
- A Caneschi
- Department of Chemistry, University of Florence, Italy
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39
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Caneschi A, Dei A, Lee H, Shultz DA, Sorace L. Ferromagnetically coupled bis(semiquinone) ligand enforces high-spin ground states in bis-metal complexes. Inorg Chem 2001; 40:408-11. [PMID: 11170550 DOI: 10.1021/ic000440r] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A Caneschi
- Dipartimento di Chimica dell'Università, Via Maragliano 75-50144, Firenze, Italy
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Chiorescu I, Giraud R, Jansen AG, Caneschi A, Barbara B. Phonon-assisted tunneling in the quantum regime of Mn12 acetate. Phys Rev Lett 2000; 85:4807-4810. [PMID: 11082657 DOI: 10.1103/physrevlett.85.4807] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2000] [Indexed: 05/23/2023]
Abstract
Longitudinal or transverse magnetic fields applied on a crystal of Mn12 acetate allows one to observe independent tunnel transitions between m = -S+p and m = S-n-p ( n = 6-10, p = 0-2 in longitudinal field and n = p = 0 in transverse field). We observe a smooth transition (in longitudinal) from coherent ground-state to thermally activated tunneling. Furthermore, two ground-state relaxation regimes show a crossover between quantum spin relaxation far from equilibrium and near equilibrium, when the environment destroys multimolecule correlations. Finally, we stress that the complete Hamiltonian of Mn12 should contain odd spin operators of low order.
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Affiliation(s)
- I Chiorescu
- Laboratoire de Magnetisme Louis Neel CNRS, BP166, 38042 Grenoble, Cedex-09, France
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Pontillon Y, Bencini A, Caneschi A, Dei A, Gatteschi D, Gillon B, Sangregorio C, Stride J, Totti F. Spin-Density Map of the Triplet Ground State of a Titanium(IV) Complex with Schiff-Base Diquinone Radical Ligands: An Investigation Using Polarized-Neutron Diffraction and Density-Functional Theory This work was supported by the 3MD EU network (contract ERB 4061 PL 97-0197). Angew Chem Int Ed Engl 2000; 39:1786-1788. [PMID: 10934361 DOI: 10.1002/(sici)1521-3773(20000515)39:10<1786::aid-anie1786>3.0.co;2-i] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Y Pontillon
- Dipartimento di Chimica Università degli Studi di Firenze Via Maragliano 77, 50144 Florence (Italy)
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Braga D, Maini L, Prodi L, Caneschi A, Sessoli R, Grepioni F. Anions derived from squaric acid form interionic pi-stack and layered, hydrogen-bonded superstructures with organometallic sandwich cations: the magnetic behaviour of crystalline. Chemistry 2000; 6:1310-7. [PMID: 10840952 DOI: 10.1002/(sici)1521-3765(20000417)6:8<1310::aid-chem1310>3.0.co;2-t] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Depending on the stoichiometric ratio, squaric acid (3,4-dihydroxy-3-cyclobutene-1,2-dione, H2SQA) reacts with [(eta6-C6H6)2Cr] in THF to form the crystalline material [(eta6-C6H6)2Cr][HSQA] (1) and in water to yield [[(eta6-C6H6)2Cr]2][SQA] x 6H2O (3); it also reacts with [(eta5-C5H5)2Co][OH] in water to form [[(eta5-C5H5)2Co]2][SQA] x 6H2O (4). Compound 1 is almost isostructural with the previously reported salt [(eta5-C5H5)2Co][HSQA] (2); its structure is based on pi-pi stacks between the benzene ligands and the hydrogen squarate anionic chains (pi-pi distance 3.375 A). Compounds 3 and 4 are isomorphous and have a structure in which layers of organometallic cations intercalate with layers of water molecules hydrogen bonded to squarate dianions. All crystals contain charge-assisted C-Hdelta+...Odelta- hydrogen bonds between the organometallic and the organic components, while negative O-H(-)...O(-) and O-H...O(2-) interactions are present in the pairs 1/3 and 2/4, respectively. In constrast to most organic salts of [(eta6-C6H6)2Cr]+ and [(eta5-C5H5)2Co]+ which are yellow, crystals of compounds 1-4 are orange. Reflectance spectra measured on the crystalline material 1 show the presence of an intense tail that can be assigned to a charge-transfer transition through the [(eta6-C6H6)2Cr]+/[HSQA]- pi-stacking interactions, while the pi stacking in 2 causes only a broadening of the band. The magnetic behaviour of 1 and 3 has been investigated by SQUID magnetometry. Both compounds are characterised by a weak antiferromagnetic interaction between the S=1/2 Cr centres of the [(eta6-C6H6)2Cr]+ cations, which is significantly stronger in 1 due to the pi-stacking with the HSQA- anions.
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Affiliation(s)
- D Braga
- Dipartimento di Chimica G. Ciamician, Universita di Bologna, Italy.
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Wernsdorfer W, Caneschi A, Sessoli R, Gatteschi D, Cornia A, Villar V, Paulsen C. Effects of nuclear spins on the quantum relaxation of the magnetization for the molecular nanomagnet Fe8. Phys Rev Lett 2000; 84:2965-2968. [PMID: 11018987 DOI: 10.1103/physrevlett.84.2965] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/1999] [Indexed: 05/23/2023]
Abstract
The strong influence of nuclear spins on resonant quantum tunneling in the molecular cluster Fe8 is demonstrated for the first time by comparing the relaxation rate of the standard Fe8 sample with two isotopic modified samples: (i) 56Fe is replaced by 57Fe, and (ii) a fraction of 1H is replaced by 2H. By using a recently developed "hole digging" method, we measured an intrinsic broadening which is driven by the hyperfine fields. Our measurements are in good agreement with numerical hyperfine calculations. For T>1.5 K, the influence of nuclear spins on the relaxation rate is less important, suggesting that spin-phonon coupling dominates the relaxation rate.
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Affiliation(s)
- W Wernsdorfer
- Laboratoire L. Neel, associe a l'UJF, CNRS, BP 166, 38042 Grenoble Cedex 9, France
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Barra AL, Caneschi A, Cornia A, Fabrizi de Biani F, Gatteschi D, Sangregorio C, Sessoli R, Sorace L. Single-Molecule Magnet Behavior of a Tetranuclear Iron(III) Complex. The Origin of Slow Magnetic Relaxation in Iron(III) Clusters. J Am Chem Soc 1999. [DOI: 10.1021/ja9818755] [Citation(s) in RCA: 402] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A. L. Barra
- Contribution from the Department of Chemistry, University of Florence, Via Maragliano 77, I-50144 Firenze, Italy, Department of Chemistry, University of Modena, Via G. Campi 183, I-41100 Modena, Italy, and High Magnetic Field Laboratory, MPI-CNRS, B.P. 166, 38042 Grenoble, France
| | - A. Caneschi
- Contribution from the Department of Chemistry, University of Florence, Via Maragliano 77, I-50144 Firenze, Italy, Department of Chemistry, University of Modena, Via G. Campi 183, I-41100 Modena, Italy, and High Magnetic Field Laboratory, MPI-CNRS, B.P. 166, 38042 Grenoble, France
| | - A. Cornia
- Contribution from the Department of Chemistry, University of Florence, Via Maragliano 77, I-50144 Firenze, Italy, Department of Chemistry, University of Modena, Via G. Campi 183, I-41100 Modena, Italy, and High Magnetic Field Laboratory, MPI-CNRS, B.P. 166, 38042 Grenoble, France
| | - F. Fabrizi de Biani
- Contribution from the Department of Chemistry, University of Florence, Via Maragliano 77, I-50144 Firenze, Italy, Department of Chemistry, University of Modena, Via G. Campi 183, I-41100 Modena, Italy, and High Magnetic Field Laboratory, MPI-CNRS, B.P. 166, 38042 Grenoble, France
| | - D. Gatteschi
- Contribution from the Department of Chemistry, University of Florence, Via Maragliano 77, I-50144 Firenze, Italy, Department of Chemistry, University of Modena, Via G. Campi 183, I-41100 Modena, Italy, and High Magnetic Field Laboratory, MPI-CNRS, B.P. 166, 38042 Grenoble, France
| | - C. Sangregorio
- Contribution from the Department of Chemistry, University of Florence, Via Maragliano 77, I-50144 Firenze, Italy, Department of Chemistry, University of Modena, Via G. Campi 183, I-41100 Modena, Italy, and High Magnetic Field Laboratory, MPI-CNRS, B.P. 166, 38042 Grenoble, France
| | - R. Sessoli
- Contribution from the Department of Chemistry, University of Florence, Via Maragliano 77, I-50144 Firenze, Italy, Department of Chemistry, University of Modena, Via G. Campi 183, I-41100 Modena, Italy, and High Magnetic Field Laboratory, MPI-CNRS, B.P. 166, 38042 Grenoble, France
| | - L. Sorace
- Contribution from the Department of Chemistry, University of Florence, Via Maragliano 77, I-50144 Firenze, Italy, Department of Chemistry, University of Modena, Via G. Campi 183, I-41100 Modena, Italy, and High Magnetic Field Laboratory, MPI-CNRS, B.P. 166, 38042 Grenoble, France
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S. Sall A, Gaye M, Sarr O, Caneschi A, Di Noto V, Vidali M. Preparation of the New Binucleating Ligand 2,6-Bis(carboxymethylsulfanylmethyl)-4-methylphenol and its Mono- and Bi-nuclear Complexes. J Chem Res (S) 1997. [DOI: 10.1039/a701315i] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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47
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Bartolomé F, Bartolomé J, Benelli C, Caneschi A, Gatteschi D, Paulsen C, Pini MG, Rettori A, Sessoli R, Volokitin Y. Effect of Chiral Domain Walls on the Specific Heat of Gd(hfac)3NITR (R=Ethyl,Isopropyl,Methyl,Phenyl) Molecular Magnetic Chains. Phys Rev Lett 1996; 77:382-385. [PMID: 10062437 DOI: 10.1103/physrevlett.77.382] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Bandinelli G, Lagi A, Caneschi A, Urso C. [Physical exercise and increase in arterial pressure and temperature in a female heterozygote for anhidrotic ectodermal dysplasia]. Ann Ital Med Int 1996; 11:59-61. [PMID: 8645533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A 51-year-old woman suffered from an increase in body temperature from 37 degrees to 38.4 degrees C after physical exercise. She did not sweat. The patient also had labile hypertension with maximum values reaching 210/130 mmHg. Tests were carried out to explore the possibility of a link between the increase in body temperature and her hypertension. Evaluation of the patient's blood pressure and temperature changes after exercise and after environmental modification suggests a pathogenetic link between hyperthermia and hypertension.
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Affiliation(s)
- G Bandinelli
- Unità Operativa di Medicina Interna I, Ospedale S. Maria Nuova, Firenze
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Abstract
Clusters of metal ions are a class of compounds actively investigated for their magnetic properties, which should gradually change from those of simple paramagnets to those of bulk magnets. However, their interest lies in a number of different disciplines: chemistry, which seeks new synthetic strategies to make larger and larger clusters in a controlled manner; physics, which can test the validity of quantum mechanical approaches at the nanometer scale; and biology, which can use them as models of biomineralization of magnetic particles.
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Goldberg D, Caneschi A, Lippard S. Synthesis and magnetochemistry of a new decanuclear manganese complex. J Inorg Biochem 1993. [DOI: 10.1016/0162-0134(93)85514-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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