English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/147810
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Intracluster interactions in butterfly {Fe3 LnO2} molecules with the non-Kramers ions Tb(III) and Ho(III)

AutorBadía-Romano, L.; Rubín, Javier; Bartolomé, Fernando; Bartolomé, Juan; Luzón, Javier; Prodius, D.; Mereacre, V.; Wilhelm, F.; Rogalev, A.
Fecha de publicación2015
EditorAmerican Physical Society
CitaciónPhysical Review B 92(6): 064411 (2015)
ResumenThe intracluster exchange interactions within the >butterfly> [Fe3Ln(μ3-O)2(CCl3COO)8(H2O)(THF)3] molecules, where Ln(III) represents a lanthanide cation, have been determined by a combination of x-ray magnetic circular dichroism (XMCD) and vibrating sample magnetometry (VSM) along with an interaction model. We have studied the compounds with Ln=Tb and Ho, both non-Kramers lanthanides and with high uniaxial anisotropy, and Ln=Lu(III) and Y(III) as pseudolanthanides, which supply nonmagnetic Ln reference cases. At low temperature, the three Fe atoms can be considered as a self-unit with total spin SFe3=5/2. Using the element selectivity of the XMCD magnetometry, measured at the Ln L2,3 edges, together with the VSM measurements, the local magnetization of the Ln ion and the Fe3 subcluster, as a function of the field and low temperature (T≈2.5K), has been determined separately. These results are described quantitatively in the framework of a theoretical model based on an effective spin Hamiltonian, which considers the competing effects of intracluster interactions and the external applied magnetic field. The Ln-Fe3 exchange interaction within the {Fe3LnO2} cluster has been determined to be antiferromagnetic, in both Tb and Ho compounds, with JFeTb/kB=-0.13(1)K and JFeHo/kB=-0.18(1)K, respectively. In both cases, a field-induced reorientation of the Fe3 and Ln spins from antiparallel to parallel orientation takes place at a threshold field μ0H=1.1 and 2 T, for the {Fe3TbO2} and {Fe3HoO2} compounds, respectively. By comparison with other compounds of the series with uniaxial anisotropy, it is concluded that the polarizability of the Fe3 subcluster magnetic moment decreases in the trend {Fe3YO2}→{Fe3TbO2}→{Fe3HoO2}→{Fe3DyO2}, because of the increasing opposition of the exchange antiferromagnetic field caused by the Ln ion. In the Ln=Tb, Ho, and Dy, the magnetization of the whole molecule is dominated by the anisotropy of the Ln ion. The intracluster Fe3-Ln exchange interactions are very weak compared to the Ln ligand field and Fe-Fe exchange interactions.
Versión del editorhttp://dx.doi.org/10.1103/PhysRevB.92.064411
Identificadoresdoi: 10.1103/PhysRevB.92.064411
issn: 2469-9950
e-issn: 2469-9969
Aparece en las colecciones: (ICMA) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
TByHOIII.pdf816,2 kBAdobe PDFVista previa
Mostrar el registro completo

NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.