Inelastic neutron scattering studies on the odd-membered antiferromagnetic wheel Cr8Ni - Université de Rennes Accéder directement au contenu
Article Dans Une Revue Physical Review B: Condensed Matter and Materials Physics (1998-2015) Année : 2012

Inelastic neutron scattering studies on the odd-membered antiferromagnetic wheel Cr8Ni

Stergios Piligkos
  • Fonction : Auteur
  • PersonId : 875867
Olivier Cador
Roberta Sessoli
  • Fonction : Auteur
  • PersonId : 847429
Hogni Weihe
  • Fonction : Auteur
  • PersonId : 860995

Résumé

[(iC3H7)2NH2][Cr8NiF9(O2CCMe)18], or Cr8Ni, is a prominent example of an odd-membered antiferromagnetic "wheel." A detailed characterization of the magnetic properties of Cr8Ni has been conducted. Inelastic neutron scattering (INS) is used to investigate the energy and momentum transfer dependence of the low-lying spin excitations, including excited states inaccessible by other experimental techniques. The richness of the INS data, in conjunction with microscopic spin Hamiltonian simulations, enables an accurate characterization of the magnetic properties of Cr8Ni. Nearest-neighbor exchange constants of JCrCr = 1.31 meV and JCrNi = 3.22 meV are determined, and clear evidence of axial single-ion anisotropy is found. The parameters determined by INS are shown to fit magnetic susceptibility. The spectroscopic identification of several successive S=1 excited total spin states and lowest spin band excitations show that the rotational band picture, valid for bipartite AFM wheels, breaks down for this odd-numbered wheel. The exchange constants determined here differ from previous efforts based on bulk measurements, and possible reasons are discussed. The large JCrNi/JCrCr ratio in Cr8Ni puts this wheel into a regime with strong quantum fluctuations in which the ground state can be described with a valence bond solid state picture.
Fichier principal
Vignette du fichier
PhysRevB.86.064405.pdf (1.27 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte
Loading...

Dates et versions

hal-00847048 , version 1 (20-08-2013)

Identifiants

Citer

Michaël L. Baker, Oliver Waldmann, Stergios Piligkos, Roland Bircher, Olivier Cador, et al.. Inelastic neutron scattering studies on the odd-membered antiferromagnetic wheel Cr8Ni. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2012, 86 (6), pp.064405/1-064405/11. ⟨10.1103/PhysRevB.86.064405⟩. ⟨hal-00847048⟩
235 Consultations
344 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More