Repozytorium

Synthesis and magneto-structural studies on a new family of carbonato bridged 3d–4f complexes featuring a [Co3II Ln3III (CO3)] (Ln = La, Gd, Tb, Dy and Ho) core: slow magnetic relaxation displayed by the cobalt(II)–dysprosium(III) analogue.

Autorzy

Mithun Chandra Majee

Sk Md Towsif Abtab

Dhrubajyoti Mondal

Manoranjan Maity

Marek Weselski

Maciej Witwicki

Alina Bieńko

Michał Antkowiak

Grzegorz Kamieniarz

Muktimoy Chaudhury

Rok wydania

2018

Czasopismo

Dalton Transactions

Numer woluminu

47

Strony

3425-3439

DOI

10.1039/c7dt04389a

Kolekcja

Naukowa

Język

Angielski

Typ publikacji

Artykuł

Streszczenie

A new family of [3 + 3] hexanuclear 3d–4f complexes [(μ3-CO3){CoIILnIIIL(μ3-OH)(OH2)}3]-(ClO4mC2H5OH·nH2O (1–5) [Ln = La (1), Gd (2), Tb (3), Dy (4), and Ho (5)] have been prepared in moderate to high yields (62–78%) following a self-assembly reaction between the ligand 6,6′,6′′-(nitrilotris(methylene))tris-(2-methoxy-4-methylphenol) (H3L), Co(OAc)2·4H2O and the lanthanide ion precursors in the mandatory presence of tetrabutylammonium hydroxide. During the reaction, atmospheric carbon dioxide is fixed in the product molecule as a bridging carbonato ligand which connects all the three lanthanide centers of this molecular assembly through a rare η222–μ3 mode of bridging as revealed from X-ray crystallography. The metal centers in all these compounds, except the GdIII analogue (2), are coupled in antiferromagnetic manner while the nature of coupling in the CoII3GdIII3 complex is ferromagnetic. DFT calculations revealed that this ferromagnetic interaction occurs most likely by the CoII–GdIII superexchange, mediated via the bridging oxygen atoms. Only the CoII–DyIII compound (4) displayed a slow relaxation of the magnetization at a very low temperature as established by AC susceptibility measurements. The data provides an estimation of the activation energy U/kB = 9.2 K and the relaxation time constant τ0 = 1.0 × 10−7 s.

Adres publiczny

http://dx.doi.org/10.1039/c7dt04389a

Strona internetowa wydawcy

https://www.rsc.org/

Podobne publikacje
2024

Effect of diamagnetic Zn(II) ions on the SMM properties of a series of trinuclear ZnDy2 and tetranuclear Zn2Dy2 (LnIII = Dy, Tb, Gd) complexes: combined experimental and theoretical studies

Shukla Pooja, Tarannum Ibtesham, Roy Soumalya, Rajput Amit, Lama Prem, Singh Saurabh Kumar, Kłak Julia, Lee Junseong, Das Sourav