Author: Rafael Moreno-esparza

Electronic Structure Modulation in an Exceptionally Stable Non-Heme Nitrosyl Iron(II) Spin-Crossover Complex

2016

The highly stable nitrosyl iron(II) mononuclear complex [Fe(bztpen)(NO)](PF6)(2) (bztpen=N-benzyl-N,N',N'-tris(2-pyridylmethyl)ethylenediamine) displays an S=1/2 S=3/2 spin crossover (SCO) behavior (T-1/2=370 K, Delta H= 12.48 kJmol(-1), Delta S=33 JK(-1) mol(-1)) stemming from strong magnetic coupling between the NO radical (S=1/2) and thermally interconverted (S=0 S=2) ferrous spin states. The crystal structure of this robust complex has been investigated in the temperature range 120-420 K affording a detailed picture of how the electronic distribution of the t(2g)-e(g) orbitals modulates the structure of the {FeNO}(7) bond, providing valuable magneto-structural and spectroscopic correlat…

Spin statesIronInorganic chemistryAntiferromagnetic couplingEthylenediamineCrystal structureElectronic structure010402 general chemistry01 natural sciencesCatalysisFerrouschemistry.chemical_compoundAtomic orbitalSpin crossover[CHIM.COOR]Chemical Sciences/Coordination chemistryMolecular structures010405 organic chemistryEstructura molecularOrganic ChemistryNitric oxideGeneral ChemistryAtmospheric temperature rangeSpin crossoverÒxid nítric0104 chemical sciences3. Good healthCrystallographychemistryFISICA APLICADANitrosyl complexesMolecular structureFerroChemistry - A European Journal

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A new N6 hexadentate ligand and a novel heptacoordinated N6O-type Fe(III) compounds: Synthesis, characterization and structure of [Fe(dimpyen)(OH)](A…

2011

Abstract In this contribution, we report the syntheses of a novel N6 donor set ligand, dimpyen = N1,N2-di[(1-methyl-1H-2-imidazolyl) methyl]-N1,N2-di(2-pyridilmethyl)-1,2-ethanediamine. This type of ligand was designed to modulate the properties of the metal ions bound to it. The reaction with Fe(II) gives off a new heptacoordinated iron(III) complex. We study the spectroscopic (UV–Vis), magnetic and electrochemical behavior and also made the structural determination with X-ray diffraction at 134 K and a heptacoordinated N6O-type derivative of Fe(III) is reported as well. This complex crystallize as perchlorate or hexafluorophosphate and the formula of these derivatives are [Fe(dimpyen)(OH)…

LigandMetal ions in aqueous solutionInorganic chemistryCrystal structureElectrochemistryInorganic Chemistrychemistry.chemical_compoundPerchlorateCrystallographyPentagonal bipyramidal molecular geometrychemistryOctahedronHexafluorophosphateMaterials ChemistryPhysical and Theoretical ChemistryInorganica Chimica Acta

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Spin crossover behavior in a series of iron(III) alkoxide complexes.

2015

The synthesis, crystal structures, magnetic behavior, and electron paramagnetic resonance studies of five new FeIII spin crossover (SCO) complexes are reported. The [FeIIIN5O] coordination core is constituted of the pentadentate ligand bztpen (N5) and a series of alkoxide anions (ethoxide, propoxide, n-butoxide, isobutoxide, and ethylene glycoxide). The methoxide derivative previously reported by us is also reinvestigated. The six complexes crystallize in the orthorhombic Pbca space group and show similar molecular structures and crystal packing. The coordination octahedron is strongly distorted in both the high- and low-temperature structures. The structural changes upon spin conversion ar…

FE(3-OET-SALAPA)2>(CLO4).SInorganic chemistryFERRIC COMPLEXESCrystal structureMethoxideLIGAND; SYSTEMMAGNETIC-SUSCEPTIBILITYlaw.inventionInorganic Chemistrychemistry.chemical_compoundlawSpin crossoverPhysical and Theoretical ChemistryElectron paramagnetic resonanceSchiff baseLigandIRONCrystallographySOLID-STATEchemistryFISICA APLICADAAlkoxideMOSSBAUEROrthorhombic crystal systemPHASE-TRANSITIONSLIGANDSYSTEMSOLVATEInorganic chemistry

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Solid- and solution-state studies of the novel mu-dicyanamide-bridged dinuclear spin-crossover system {[(Fe(bztpen)]2[mu-N(CN)2]}(PF6)3 x n H2O.

2005

The mononuclear diamagnetic compound {Fe(bztpen)[N(CN)2]} (PF6)CH3OH (1) (bztpen = N-benzyl-N,N′,N′- tris(2-pyridylmethyl)ethylenediamine) has been synthesized and its crystal structure studied. Complex 1 can be considered to be the formal pre-cursor of two new dinuclear, dicyanamide-bridged iron(II) complexes with the generic formula {[(Fe(bztpen)]2[μN(CN)2]}(PF6) 3·nH2O (n = 1 (2) or 0 (3)), which have been characterized in the solid state and in solution. In all three complexes, the iron atoms have a distorted [FeN6] octahedral coordination defined by a bztpen ligand and a terminal (1) or a bridging dicyanamide ligand (2 and 3). In the solid state, 2 and 3 can be considered to be molecu …

Organic ChemistrySpin transitionEthylenediamineGeneral ChemistryCrystal structureCatalysischemistry.chemical_compoundCrystallographyParamagnetismOctahedronchemistrySpin crossoverX-ray crystallographyDicyanamideChemistry (Weinheim an der Bergstrasse, Germany)

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Spin‐Crossover 2D Metal–Organic Frameworks with a Redox‐Active Ligand: [Fe(ttf‐adpy) 2 M(CN) 4 ]· n H 2 O (ttf‐adpy = 4‐Tetrathiafulvalenylcarboxamid…

2008

A new ttf (tetrathiofulvalene) ligand containing an amidopyridine moiety was synthesized and characterized. The electrochemical study of the 4-tetrathiofulvalenylcarboxamidopyridine (ttf–adpy) ligand showed two reversible oxidation processes at EI′1/2 = 0.08 V/Fc+–Fc and EII′1/2 = 0.26 V/Fc+–Fc. The crystal structure of [(ttf–adpyH)2Pt(CN)4] (1) was solved at 293 K, where 1 displays the triclinic space group P. The ttf–adpyH+ molecule is planar, and the bond lengths within the ttf core are in the usual range for neutral ttf moieties. The ttf–adpyH+ molecules and the [Pt(CN)4]2– anions organize in a three-dimensional network by means of hydrogen bonds and short S···S contacts. In the network…

Inorganic ChemistryCrystallographyChemistryHydrogen bondLigandSpin crossoverInorganic chemistrySpin transitionMoleculeMetal-organic frameworkCrystal structureAcceptorEuropean Journal of Inorganic Chemistry

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