Abstract
Three new 3 d–4 f complexes of general formula trans-[MF2(py)4][LnDOTA] (M=Cr3+ or Co3+, Ln=Dy3+ or Y3+, py=pyridine and DOTA=tetraazacyclododecane-N,N′,N′′,N′′′-tetraacetate) have been synthetised. The fluoride-bridged systems were designed to achieve perfect tetragonal symmetry by combining four-fold symmetric lanthanide and transition metal building blocks. From single crystal measurements, an unprecedented switch of the tetragonal anisotropy of the Dy3+ complexes has been observed. A combination of spectroscopic observations, magnetometry measurements and ab initio calculations allowed us to pinpoint the origin of this phenomenon, which is related to the peculiar energy level structure of the complexes. Moreover, the fourfold anisotropy of the complex has been exploited to design a rotating magnetocaloric experiment showing that tetragonal anisotropy holds great potential to engineer a new class of more efficient magnetic refrigerants.
Original language | English |
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Article number | e202417582 |
Journal | Angewandte Chemie - International Edition |
Volume | 64 |
Issue number | 5 |
Number of pages | 10 |
ISSN | 1433-7851 |
DOIs | |
Publication status | Published - 2024 |
Bibliographical note
Funding Information:This work was funded by the European Union (ERC, ELECTRA, 101039890). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. The financial support provided by the MUR\u2014Dipartimenti di Eccellenza 2023\u20132027 (DICUS 2.0) (ref. no. B96C1700020008) to the Department of Chemistry \u201CUgo Schiff\u201D of the University of Florence is acknowledged. JB acknowledges support from the Independent Research Fund Denmark (1026\u201000082B). PK acknowledges support from the National Science Centre (Poland) grant SONATA no. (2018/31/D/ST8/02118). Dr. Gemma K. Gransbury is kindly acknowledged for proofreading. Prof. K. Bernot is kindly acknowledged for scientific discussion. Open Access publishing facilitated by Universit\u00E0 degli Studi di Firenze, as part of the Wiley \u2010 CRUI\u2010CARE agreement.
Publisher Copyright:
© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.
Keywords
- lanthanide complexes
- magnetic anisotropy switch
- molecular magnetism
- rotating magnetocaloric effect