Magnetic chains of Fe3 clusters in the {Fe3YO2} butterfly molecular compound

Rubín, Javier (Universidad de Zaragoza) ; Badía-Romano, Laura (Universidad de Zaragoza) ; Luis, Fernando (Universidad de Zaragoza) ; Mereacre, Valeriu ; Prodius, Denis ; Arauzo, Ana (Universidad de Zaragoza) ; Bartolomé, Fernando (Universidad de Zaragoza) ; Bartolomé, Juan (Universidad de Zaragoza)

Resumen: The "butterfly" molecule [Fe3Y(µ3-O)2(CCl3COO)8(H2O)(THF)3] (in brief {Fe3YO2}) includes three Fe3+ ions which build a robust Fe3 cluster with a strong intracluster antiferromagnetic exchange and a total spin S = 5/2. It represents the starting magnetic system to study further interactions with magnetic rare earths when Y is replaced with lanthanides. We present heat capacity and equilibrium susceptibility measurements below 2 K, which show that each cluster has a sizeable magnetic anisotropy pointing to the existence of intercluster interactions. However, no phase transition to a long-range magnetically ordered phase is observed down to 20 mK. The intercluster interaction is analysed in the framework of the one-dimensional Blume-Capel model with an antiferromagnetic chain interaction constant J/kB = -40(2) mK between Fe3 cluster spins, and a uniaxial anisotropy with parameter D/kB = -0.56(3) K. This is associated to single chains of Fe3 clusters oriented along the shortest intercluster distances displayed by the crystal structure of {Fe3YO2}. Ac susceptibility measurements reveal that the magnetic relaxation is dominated by a quantum tunnelling process below 0.2 K, and by thermally activated processes above this temperature. The experimental activation energy of this single chain magnet, Ea/kB = 3.4(6) K, can be accounted for by the combination of contributions arising from single-molecule magnetic anisotropy and spin-spin correlations along the chains.

Idioma: Inglés

DOI: 10.1039/c9dt04816b

Año: 2020

Publicado en: Dalton Transactions 49, 9 (2020), 2979-2988
ISSN: 1477-9226

Factor impacto JCR: 4.39 (2020)

Categ. JCR: CHEMISTRY, INORGANIC & NUCLEAR rank: 8 / 45 = 0.178 (2020) - Q1 - T1

Factor impacto SCIMAGO: 0.98 - Inorganic Chemistry (Q1)

Financiación: info:eu-repo/grantAgreement/ES/DGA/E09-17R
Financiación: info:eu-repo/grantAgreement/ES/DGA/E12-R17
Financiación: info:eu-repo/grantAgreement/ES/MCINN/MAT2017-83468-R
Financiación: info:eu-repo/grantAgreement/ES/MCINN/PCI2018-093116
Financiación: info:eu-repo/grantAgreement/ES/MICINN/RTI2018-096075-B-C21
Financiación: info:eu-repo/grantAgreement/EUR/MOLSPIN-COST/CA15128

Tipo y forma: Artículo (PostPrint)

Área (Departamento): Área Cienc.Mater. Ingen.Metal. (Dpto. Ciencia Tecnol.Mater.Fl.)
Área (Departamento): Área Física Materia Condensada (Dpto. Física Materia Condensa.)