@article{a2dbe019bb534e83bba58228a3eb06c2,
title = "Anisotropic exchange interaction and field-induced SMM behaviour in a mixed valence {CoII4 CoIII2} complex",
abstract = "We are reporting the synthesis and structural characterization of a new hexanuclear Co(ii)/Co(iii) complex starting from a versatile pivalate cobalt precursor and the racemic mixture of a chelating Schiff base type ligand. The main [CoII4 CoIII2(μ3-OH)2(μ-OR)2(μ-OR′)2(μ-OR′′)2]6+core is unprecedented and exhibits an inversion center that affords only two unique Co(ii) sites. We performed DC and AC magnetic measurements and analysed them in terms of the anisotropic exchange of ground Kramers doublets at each Co(ii) site due to their unquenched angular orbital contribution to the magnetic moment. Quantum computations support the experimental data treatment. The interplay of dominant antiferromagnetic exchange, inversion symmetry and a non-collinear main quantization axis affords an exchange energy spectrum with mostly non-magnetic states. Nevertheless, field induced SMM behaviour is observed at 1500 Oe and below 3 K which might be explained by the relaxation of the first excited magnetic state (which is populated enough) through the next closest excited state. The Orbach and/or Raman mechanism could be operative from the experimental and quantum computed results.",
author = "Daiana Cabrosi and Carlos Cruz and Ver{\'o}nica Paredes-Garc{\'i}a and Pablo Albor{\'e}s",
note = "Funding Information: We gratefully acknowledge UBA, ANPCYT and CONICET for funding resources. PA is a staff member of CONICET and DC is a doctoral fellowship of CONICET. The authors gratefully acknowledge the computing time granted on the supercomputer MOGON at Johannes Gutenberg University Mainz (hpc.uni-mainz.de). The XRD diffraction experiments were performed under proposals 20180504 and 20190182 of the LNLS (Brazilian National Laboratory of Synchrotron Radiation, Campinas, Brazil). We specially thank Dr Ana Carolina de Mattos Zeri and Andrey Fabricio Ziem Nascimento for their assistance provided for the synchrotron experiments and data processing and Dr Florencia Di Salvo and Lic. Federico Movilla for XRD sample mounting and data collection. VPG acknowledges CONICYT-FONDEQUIP/PPMS/EQM130086-UNAB, Chilean-French International Associated Laboratory for Multifunctional Molecules and Materials-LIAM3-CNRS no. 1027, and Financiamiento Basal, AFB180001, CEDENNA. Publisher Copyright: {\textcopyright} The Royal Society of Chemistry 2021. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.",
year = "2021",
month = jan,
day = "28",
doi = "10.1039/d0dt03075a",
language = "English",
volume = "50",
pages = "1402--1412",
journal = "Dalton Transactions",
issn = "1477-9226",
publisher = "Royal Society of Chemistry",
number = "4",
}