Afficher la notice abrégée

The key role of the intermolecular π−π interactions in the presence of spin crossover in neutral [Fe(abpt)2A2] complexes (A = terminal monoanion N ligand)

hal.structure.identifierChimie, Electrochimie Moléculaires et Chimie Analytique [CEMCA]
dc.contributor.authorDUPOUY, Gaelle
hal.structure.identifierChimie, Electrochimie Moléculaires et Chimie Analytique [CEMCA]
dc.contributor.authorMARCHIVIE, Mathieu
hal.structure.identifierChimie, Electrochimie Moléculaires et Chimie Analytique [CEMCA]
dc.contributor.authorTRIKI, Smail
hal.structure.identifierChimie, Electrochimie Moléculaires et Chimie Analytique [CEMCA]
dc.contributor.authorSALA-PALA, Jean
hal.structure.identifierChimie, Electrochimie Moléculaires et Chimie Analytique [CEMCA]
dc.contributor.authorSALAÜN, Jean-Yves
hal.structure.identifierInstituto de Ciencia Molecular [ICMol]
dc.contributor.authorGOMEZ-GARCIA, Carlos
hal.structure.identifierInstitut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
dc.contributor.authorGUIONNEAU, Philippe
dc.date.issued2008
dc.identifier.issn0020-1669
dc.description.abstractEnNew iron(II) complexes of formulas [Fe(abpt)2(tcm)2] (1), [Fe(abpt)2(tcnome)2] (2), and [Fe(abpt)2(tcnoet)2] (3) (abpt = 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole, tcm− = [C(CN)3]− = tricyanomethanide anion; tcnome− = [(NC)2CC(OCH3)C(CN)2]− = 1,1,3,3-tetracyano-2-methoxypropenide anion; tcnoet− = [(NC)2CC(OC2H5)C(CN)2]− = 1,1,3,3-tetracyano-2-ethoxypropenide anion) have been synthesized and characterized by infrared spectroscopy, magnetic properties and by variable-temperature single-crystal X-ray diffraction. The crystal structure determinations of 1 and 2 reveal in both cases centrosymmetric discrete iron(II) monomeric structures in which two abpt chelating ligands stand in the equatorial plane and two terminal polynitrile ligands complete the distorted octahedral environment in trans positions. For 3, the crystallographic studies revealed two polymorphs, 3-A and 3-B, exhibiting similar discrete molecular structures to those found for 1 and 2 but with different molecular arrangements. In agreement with the variable-temperature single-crystal X-ray diffraction, the magnetic susceptibility measurements, performed in the temperature range 2−400 K, showed a spin-crossover phenomenon above room temperature for complexes 1, 3-A, and 3-B with a T1/2 of 336, 377, and 383 K, respectively, while complex 2 remains in the high-spin ground state (S = 2) in the whole temperature range. To understand further the magnetic behaviors of 1, 3-A, and 3-B, single-crystal X-ray diffraction measurements were performed at high temperatures. The crystal structures of both polymorphs could not be obtained above 400 K because the crystals decomposed. However, single-crystal X-ray data have been collected for compound 1, which reaches the full high-spin state at lower temperatures. Its crystal structure, solved at 400 K, showed a strong modification of the iron coordination sphere (average Fe−N = 2.157(3) Å vs 1.986(3) Å at 293 K). In agreement with the magnetic properties. Such structural behavior is a signature of the spin-state transition from low-spin (LS) to high-spin (HS). On the basis of the intermolecular π stacking observed for the series described in this paper and for related complexes involving similar discrete structures, we have shown that complexes displaying frontal π stacking present spin transition such as 1, 3-A, and 3-B and those involving sideways π stacking such as complex 2 remain in the HS state.
dc.language.isoen
dc.publisherAmerican Chemical Society
dc.subject.enSpin-crossover
dc.subject.enIron(II)
dc.subject.enStructure-properties
dc.subject.enCrystal structure
dc.title.enThe key role of the intermolecular π−π interactions in the presence of spin crossover in neutral [Fe(abpt)2A2] complexes (A = terminal monoanion N ligand)
dc.typeArticle de revue
dc.identifier.doi10.1021/ic800955r
dc.subject.halChimie/Matériaux
bordeaux.journalInorganic Chemistry
bordeaux.page8921-8931
bordeaux.volume47
bordeaux.issue19
bordeaux.peerReviewedoui
hal.identifierhal-00326392
hal.version1
hal.popularnon
hal.audienceInternationale
hal.origin.linkhttps://hal.archives-ouvertes.fr//hal-00326392v1
bordeaux.COinSctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Inorganic%20Chemistry&rft.date=2008&rft.volume=47&rft.issue=19&rft.spage=8921-8931&rft.epage=8921-8931&rft.eissn=0020-1669&rft.issn=0020-1669&rft.au=DUPOUY,%20Gaelle&MARCHIVIE,%20Mathieu&TRIKI,%20Smail&SALA-PALA,%20Jean&SALA%C3%9CN,%20Jean-Yves&rft.genre=article


Fichier(s) constituant ce document

FichiersTailleFormatVue

Il n'y a pas de fichiers associés à ce document.

Ce document figure dans la(les) collection(s) suivante(s)

Afficher la notice abrégée