FeII(pap-5NO2)2 and FeII(qsal-5NO2)2 Schiff-Base Spin-CrossoverComplexes: A Rare Example with Photomagnetism and Room-Temperature Bistability
| Autor: | Olga Iasco, Azzedine Bousseksou, Régis Guillot, Marie-Laure Boillot, Jean-Francois Meunier, Eric Rivière, Marylise Buron-Le Cointe |
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| Přispěvatelé: | Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), 09-BLAN-0212, Agence Nationale de la Recherche, European Regional Development Fund, Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
Schiff base
010405 organic chemistry Stereochemistry Condensation Photomagnetic effect 010402 general chemistry Photomagnetism 01 natural sciences 0104 chemical sciences Inorganic Chemistry chemistry.chemical_compound Crystallography Differential scanning calorimetry chemistry Spin crossover Mössbauer spectroscopy [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci] Physical and Theoretical Chemistry Spin (physics) |
| Zdroj: | Inorganic Chemistry Inorganic Chemistry, American Chemical Society, 2015, 54 (4), pp.1791-1799. ⟨10.1021/ic5027043⟩ Inorganic Chemistry, 2015, 54 (4), pp.1791-1799. ⟨10.1021/ic5027043⟩ |
| ISSN: | 0020-1669 1520-510X |
| Popis: | International audience; We focus here on the properties of Fe complexes formed with Schiff bases involved in the chemistry of FeIII spin-transition archetypes. The neutral Fe(pap-5NO2)2 (1) and Fe(qsal-5NO2)2·Solv (2 and 2·Solv) compounds (Solv = 2H2O) derive from the reaction of FeII salts with the condensation products of pyridine-2-carbaldehyde with 2-hydroxy-5-nitroaniline (Hpap-5NO2) or 5-nitrosalicylaldehyde with quinolin-8-amine (Hqsal-5NO2), respectively. While the Fe(qsal-5NO2)2·Solv solid is essentially low spin (S = 0) and requires temperatures above 300 K to undergo a S = 0 ↔ S = 2 spin-state switching, the Fe(pap-5NO2)2 one presents a strongly cooperative first-order transition (T↓ = 291 K, T↑ = 308 K) centered at room temperature associated with a photomagnetic effect at 10 K (TLIESST = 58 K). The investigation of these magnetic behaviors was conducted with single-crystal X-ray diffraction (1, 100 and 320 K; 2, 100 K), Mössbauer, IR, UV–vis (1 and 2·Solv), and differential scanning calorimetry (1) measurements. The Mössbauer analysis supports a description of these compounds as FeII Schiff-base complexes and the occurrence of a metal-centered spin crossover process. In comparison with FeIII analogues, it appears that an expanded coordination sphere stabilizes the valence 2+ state of the Fe ion in both complexes. Strong hydrogen-bonding interactions that implicate the phenolato group bound to FeII promote the required extra-stabilization of the S = 2 state and thus determines the spin transition of 1 centered at room temperature. In the lattice, the hydrogen-bonded sites form infinite chains interconnected via a three-dimensional network of intermolecular van der Waals contacts and π–π interactions. Therefore, the spin transition of 1 involves the synergetic influence of electrostatic and elastic interactions, which cause the enhancement of cooperativity and result in the bistability at room temperature. |
| Databáze: | OpenAIRE |
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