A5060059837- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Magnetism in coordination complexes
- Lanthanide and Transition Metal Complexes
- Metal-Organic Frameworks: Synthesis and Applications
- Metal complexes synthesis and properties
- Crystallography and molecular interactions
- Electron Spin Resonance Studies
- Organic and Molecular Conductors Research
- Metal-Catalyzed Oxygenation Mechanisms
- Porphyrin and Phthalocyanine Chemistry
- Inorganic and Organometallic Chemistry
- Molecular Junctions and Nanostructures
- Magnetic properties of thin films
- Advanced NMR Techniques and Applications
- Crystal structures of chemical compounds
- Synthesis and Characterization of Heterocyclic Compounds
- Quantum and electron transport phenomena
- Chemical Synthesis and Reactions
- Polyoxometalates: Synthesis and Applications
- Sulfur-Based Synthesis Techniques
- Free Radicals and Antioxidants
- Physics of Superconductivity and Magnetism
- Nanomaterials for catalytic reactions
- Covalent Organic Framework Applications
Parc Científic de la Universitat de València
2015-2024
Universitat de València
2015-2024
Universitat Politècnica de València
2000-2023
ALBA Synchrotron (Spain)
2023
Centro Médico Sanitas Valencia
2016-2020
Universitat de Barcelona
1997-2014
Centre National de la Recherche Scientifique
1997-2011
Institut National Polytechnique de Toulouse
2011
Université Toulouse III - Paul Sabatier
2005-2011
Université de Toulouse
2011
This article reviews the most relevant chemical and structural aspects that influence spin-crossover phenomenon (SCO). Special attention is focussed on recent development of SCO coordination polymers. The different approaches currently being explored in order to achieve multifunctionality materials are discussed.
The compound [Fe(tvp)(2)(NCS)(2)] . CH(3)OH, where tvp is 1,2-di-(4-pyridyl)-ethylene, has been synthesized and characterized by x-ray single-crystal diffraction. It consists of two perpendicular, two-dimensional networks organized in parallel stacks sheets made up edge-shared [Fe(II)](4) rhombuses. fully interlocked define large square channels the [001] direction. Variable-temperature magnetic susceptibility measurements Mössbauer studies reveal that this shows low-spin to high-spin...
The ins and outs of spin: Using the microporous coordination polymer {Fe(pz)[Pt(CN)(4)]} (1, pz=pyrazine), incorporating spin-crossover subunits, two-directional magnetic chemo-switching is achieved at room temperature. In situ measurements following guest vapor injection show that most molecules transform 1 from low-spin (LS) state to high-spin (HS) state, whereas CS(2) uniquely causes reverse HS-to-LS transition.
The three-dimensional polymeric compounds [Fe(pz)M(CN)4]·nH2O (pz = pyrazine; M Ni(II), Pd(II), and Pt(II)) have been synthesized characterized. They undergo strong cooperative spin transitions, large hysteresis loops, dramatic color changes upon conversion. two-dimensional homologues [Fe(py)2M(CN)4] (py pyridine; also In the latter case cooperativity is smaller than in tri-dimensional derivatives, consequently narrower loops were observed.
Nanocrystals of the three-dimensional, spin-crossover, porous coordination framework [Fe(pz)Pt(CN)4]⋅n H2O (pz=pyrazine; n≤2.5) have been synthesized from water-in-oil microemulsions. The surfactant-free nanocrystals readily desorb water and resulting anhydrous compounds exhibit thermally induced electronic bistability accompanied by a pronounced color change (see picture; HS=high spin, LS=low spin) close to room temperature.
A net change: fully reversible ligand substitution involving coordination/uncoordination of gaseous water and pyrimidine induces the repetitive allosteric transformation three interpenetrated nets into a single three-dimensional net. The does not affect crystallinity sample but alters significantly spin-crossover transition; compound shows magnetic chromatic bistability (see picture).
In the loop: A reversible spin transition was observed by Raman spectroscopy on application of a single laser pulse (8 ns) in hysteresis loop spin-crossover complex [Fe(pyrazine){Pt(CN)4}]. This bi-directional, photoinduced switching occurs at room temperature over wide region bistability and involves magnetization as well color changes (see picture).
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTwo-step spin crossover in the new dinuclear compound [Fe(bt)(NCS)2]2bpym, with bt = 2,2'-bi-2-thiazoline and bpym 2,2'-bipyrimidine: experimental investigation theoretical approachJose Antonio Real, Helene Bolvin, Azzedine Bousseksou, Ary Dworkin, Olivier Kahn, Francois Varret, Jacqueline ZarembowitchCite this: J. Am. Chem. Soc. 1992, 114, 12, 4650–4658Publication Date (Print):June 1, 1992Publication History Published online1 May 2002Published...
Assembly time: Thin films of [Fe(pyrazine){M(CN)4}] (M=Ni, Pd, or Pt) coordination polymers were assembled sequentially through coordinate bonding on gold surfaces (see scheme). These multilayers exhibit spin-crossover phenomena with hysteresis at room temperature. Supporting information for this article is available the WWW under http://www.wiley-vch.de/contents/jc_2002/2006/z601885_s.pdf from author. Please note: The publisher not responsible content functionality any supporting supplied...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructural changes associated with the spin transition in bis(isothiocyanato)bis(1,10-phenanthroline)iron: a single-crystal x-ray investigationBernard Gallois, Jose Antonio Real, Christian Hauw, and Jacqueline ZarembowitchCite this: Inorg. Chem. 1990, 29, 6, 1152–1158Publication Date (Print):March 1, 1990Publication History Published online1 May 2002Published inissue 1 March...
Micro- and nanometer-sized patterns of the spin-crossover compound Fe(pyrazine)[Pt(CN)4] have been fabricated using a combination lift-off multilayer sequential assembly methods. These (see figure inside cover) exhibit bistability their electronic states and, thus, represent novel platform for wide array potential applications.
Precise control of spin transition temperature (T(c)) is one the most important challenges in molecular magnetism. A Hofmann-type porous coordination polymer {Fe(pz)[Pt(II)(CN)(4)]} (1; pz = pyrazine) exhibited cooperative near room (T(c)(up) 304 K and T(c)(down) 284 K) its iodine adduct {Fe(pz)[Pt(II/IV)(CN)(4)(I)]} (1-I), prepared by oxidative addition to open metal sites Pt(II), raised T(c) 100 K. DSC microscopic Raman spectra a solid mixture 1-I 1 revealed that migrated from through...
Mixing with the guests: Exposure of porous spin-crossover framework {Fe(pz)[PtII(CN)4]} to X2 (pz=pyrazine; X2=Cl2, Br2, and I2) leads incorporation halides in coordinatively unsaturated [PtII(CN)4]2− moieties through oxidative addition, thus affording mixed-valence series {Fe(pz)[PtII/IV(CN)4(X)]}, which features quite distinct cooperative spin-transition properties.
Three novel three-dimensional coordination polymers, {FeII(azpy)[(MII(CN)4)]}·nH2O (azpy = 4,4′-azopyridine; M Ni, Pd, and Pt), have been synthesized as polycrystalline bulk materials continuous well nanopatterned thin films on gold substrates. Single crystals of the Pt derivative also isolated corresponding X-ray diffraction analysis at 140 K indicates that it crystallizes in tetragonal P4/mmm space group with a b 7.1670(5) Å, c 13.0330(13) V 669.40(9) Å3 Z 1. Four square-planar [Pt(CN)4]2−...
Controlling the spin of electrons in nanoscale electronic devices is one most promising topics aiming at developing with rapid and high density information storage capabilities. The interface magnetism or spinterface resulting from interaction between a magnetic molecule metal surface, vice versa, has become key ingredient creating molecular novel functionalities. Here, we present single-molecule wire that displays large (>10000%) conductance switching by controlling spin-dependent transport...
The two-dimensional spin crossover (SCO) polymers [Fe(3-Fpy)2M(CN)4] (MII = Ni(1), Pd(2), Pt(3)) were nanostructured in the form of nanocrystals and nanoparticles, their chemical, structural, physical characterization was carried out using different experimental methods (powder X-ray diffraction, magnetic susceptibility measurements, Mössbauer infrared spectroscopy, transmission scanning electronic microscopy, etc.). Surfactant-free average dimensions 400 × 30 nm (1a, 1a*, 2a, 3a)...
A quasielastic neutron scattering and solid-state (2)H NMR spectroscopy study of the polymeric spin-crossover compound {Fe(pyrazine)[Pt(CN)(4)]} shows that switching rotation a molecular fragment--the pyrazine ligand--occurs in association with change spin state. The was examined on wide time scale (10(-13)-10(-3) s) by both techniques, which clearly demonstrated combination between transition under external stimuli (temperature chemical). rings are seen to perform 4-fold jump motion about...
Abstract The synthesis and characterization of a series three‐dimensional (3D) Hofmann‐like clathrate porous metal–organic framework (MOF) materials [Fe(bpac)M(CN) 4 ] (M=Pt, Pd, Ni; bpac=bis(4‐pyridyl)acetylene) that exhibit spin‐crossover behavior is reported. rigid bpac ligand longer than the previously used azopyridine pyrazine has been selected with aim to improve both properties porosity corresponding coordination polymers (PCPs). 3D network composed successive {Fe[M(CN) ]} n planar...
Inclusion of thiourea guest molecules in the tridimensional spin crossover porous coordination polymers {[Fe(pyrazine)[M(CN)(4)]} (M = Pd, Pt) leads to novel clathrates exhibiting unprecedented large thermal hysteresis loops ca. 60 K wide centered near room temperature.
Abstract The unprecedented bimetallic 2D coordination polymer {Fe[(Hg(SCN) 3 ) 2 ](4,4′‐bipy) } n exhibits a thermal high‐spin (HS)↔low‐spin (LS) staircase‐like conversion characterized by multi‐step dependence of the HS molar fraction γ . Between fully ( =1) and LS =0) phases, two steps associated with different ordering appear in terms spin‐state concentration waves (SSCW). On ≈0.5 step, periodic SSCW forms HS‐LS‐HS‐LS sequence. ≈0.34 4D superspace crystallography structural refinement...