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Showing 1 to 20 of 39 for “"Spin-Crossover"”.
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Amphiphilic Spin Crossover Complexes
… and characterization of amphiphilic iron(II) spin crossover complexes. The prime attention was on the self-assembly ability of the synthesized compounds and the influence of the supramolecular arrangement in the solid on the SCO behaviour. The used ligand system is based on Schiff base-like …
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Spin Crossover under Extreme Conditions: A Structural Approach
… studies of several iron complexes that show spin crossover (SCO) properties are presented and intrinsic links between the structure and properties have been established for these systems. X-ray diffraction experiments of samples under extremes of temperature and pressure and after irradiation …
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ESR studies of some iron(II) spin crossover complexes.
X-band ESR powder studies have been done on the spin transition in Mn 2- doped [Fe(bpp)2][CF3SO3] 2·H2O, [Fe(bpp)2][BF4] 2 and [Fe(5NO2-sal N(1,4,7,10))] complexes. The use of Mn 2+ as an ESR probe in the studies is based on the knowledge that the ion is very sensitive to changes in its surrounding …
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Synthesis of Heteroleptic Redox-active and Spin-crossover Complexes
… redox-active complexes with the potential for spin-crossover is synthetic in nature. The intent behind incorporating the Schiff base ligand N-(8-quinolyl)salicylaldimine with some redox-active species into a mixed ligand complex featuring a d4-d7 metal ion center was to prime the material for …
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Dynamic environmental transmission electron microscopy of spin crossover materials
The work reported here focuses on the study of spin crossover (SCO) materials via dynamic transmission electron microscopy (DTEM). SCO metal complexes commonly contain first-row d4-d7 transition metals in an octahedral ligand field, which splits the d-orbitals into tripledegenerate t2g and …
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Curiosities of the Electron Dynamics of Spin-Crossover Solids (Moessbauer)
… have been prepared and their spin-crossover properties in the solid state have been characterized using variable-temperature (4.2-313 K) magnetic susceptibility, EPR spectroscopy, and ('57)Fe Mossbauer spectroscopy. For the unperturbed complex "FeP" the low-spin (LS) (DBLHARR) …
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Effect of Pressure on Intramolecular Charge-Transfer and Spin-Crossover Materials
… that can exist in either a high- or a low-spin electronic configuration. These materials are studied as crystalline solids, doped into polymers, and in solution. In general there are two aspects we consider: (1) in what way does pressure affect the electronic structure of these two classes …
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Dynamics and Mechanism of Spin-State Interconversion in Iron Spin-Crossover Complexes
… of the dynamics and mechanism of the so-called spin-crossover phenomenon. Several iron spin-crossover systems, including ferrous and ferric complexes, are investigated with various spectroscopic techniques and single-crystal X-ray structure determination.
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Novel Discoveries About the Spin-Crossover Transition in Schiff-Base Ferric Complexes
The high-spin (('6)A(,1)) to low-spin (('2)T(,2)) conversion has been studied in pseudo-octahedral ferric complexes {Fe('III) (X-SalEen)(,2)}Y. The ligand, X-SalEen, is obtained by the Schiff-base condensation of salicylaldehyde, 3-OCH(,3)-salicylaldehyde, or 5-OCH(,3)-salicylaldehyde with …
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Ultrafast optical and X-ray spectroscopy of strongly cooperative spin-crossover nanoparticles
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2024-05-01
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Synthese und Charakterisierung bi- und polynuklearer Eisen(II) Spin Crossover Komplexe zur Oberflächendeponierung
Zur Spinschaltung auf Oberflächen und zur Untersuchung von kooperativer Spinschaltung in bi- und polynuklearen Eisen(II)-Komplexen wurden die Synthesen von binuklearen Eisen(II)-Komplexen der Art [{Fe(H2B(pz)2)2}2(μ-L)] mit den bis-bidentaten Brückenliganden L = 5,5‘‘-(1,2-ethinyl)di-2,2‘-bipyridin …
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Probing the reaction coordinate of photoinduced spin-crossover with femtosecond M-edge XANES
Photoinduced spin-crossover is studied using femtosecond M-edge XANES with a tabletop instrument based on a high-harmonic generation source. This technique probes the oxidation state, spin state and ligand field of the metal center with sub-50 fs time resolution, making it a powerful tool to study …
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The Solid State Ferric Spin-Crossover Transition: Spectroscopic, Magnetic, and Structural Investigations (Moessbauer, Epr, High, Low)
A number of new ferric spin-crossover solids have been prepared and characterized by using variable temperature magnetic susceptibility, ('57)Fe Mossbauer spectroscopy, EPR spectroscopy, and single-crystal X-ray diffractometry. These solids were prepared and examined in order to determine the …
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The Role of Charge Transfer Induced Spin Crossover Complexes on Charge-Separated State Lifetime in Photoelectrochemical Devices
… photoanode constructs. Mn(pzb)2 undergoes a spin transition from a high-spin, sextet state for Mn(II), to a low-spin, triplet state for Mn(III). The spin change is induced upon a pseudo-octahedral-to-octahedral structural change that modifies the orbital overlap between the pyrazolyl lone …
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Stimuli-Responsive Metal–Organic Cages
… stimuli respectively: 1) a thermally induced spin-crossover system where spin states of the metal centers can be altered by the change of temperature; 2) a redox-active azopyridine-based system that can reversibly accept and donate electrons. In the first system, the strategy for constructing …
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Ligand design for molecule-based magnetic and/or conducting materials
… V and VI indicate that they undergo incomplete spin crossover transitions in the solid state. Strategies for the preparation of chiral spin crossover N3O2 macrocycles are discussed and the synthesis of the novel chiral Fe(II) macrocyclic complex VII is reported. Magnetic susceptibility and …
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Spin labile conducting metallopolymers : a new architecture for hybrid multifunctional materials
… SeN- (5.08), PF6- (5.09), and CI04- (5.10)]. Spin-crossover is observed in the solid state for (2.08) - (2.10) and (5.07) - (5.10), including a ve ry rare S = 5/2 to 3/2 spin-crossover in complex (2.09). The unusal reduction of complex (2.10) produces a high-spin iron(I1) complex (2.12). Six …
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High-pressure and high-temperature structural and electronic properties of (Mg,Fe)O and FeO
… was observed. At pressures higher than 50 GPa a spin-pairing transition of Fe2+ was observed. Clear and pronounced changes in the Mössbauer spectra are fully consistent with a high- to low-spin transition: the centre shift decreases, indicating an increase of electron density at the nuclei. …
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Iron spin crossovers at high pressures and temperatures and their effects on materials relevant tot he Earth’s lower mantle and core
… by mass in the Earth. The iron content and its spin or oxidation state have a major influence on the physical properties of the main phases in the Earth’s interior. Therefore it is of vast importance to understand the behavior of iron in mineral phases at the temperature and pressure conditions …
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Voltage Controlled Non-Volatile Spin State and Conductance Switching of a Molecular Thin Film Heterostructure
… room temperature, stable locking of the spin state, and the corresponding conductivity change, when molecular spin crossover thin films are deposited on a ferroelectric substrate. This opens the door to the creation of a non-volatile, room temperature, molecular multiferroic gated voltage …
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