Fine-Tuning the Single-Molecule Magnet Properties of a [Dy(III)-Radical]2 Pair
摘要:
A supramolecular species composed of a pair of nonequivalent Dy(III)-radical complexes exhibits single-molecule magnet (SMM) properties. The weak effective antiferromagnetic coupling between the Dy(III) ions can be compensated by application of a small (700 Oe) dc field, revealing the relaxation mode of the two distinct SMMs. These unique results illustrate how the dynamics of a supramolecular [Dy-Radical](2) SMM can be fine-tuned by the exchange-bias and an applied magnetic field.
Ferromagnetic ordering of –[Sm(<scp>iii</scp>)-radical]<sub>n</sub>– coordination polymers
作者:Elisabeth M. Fatila、Adam C. Maahs、Michelle B. Mills、Mathieu Rouzières、Dmitriy V. Soldatov、Rodolphe Clérac、Kathryn E. Preuss
DOI:10.1039/c6cc01548d
日期:——
A structurally characterized lanthanide-radical coordination polymer exhibits ferromagnetic ordering. Superexchange and McConnel I mechanisms are implicated.
McConnell I mechanism promotes ferromagnetic interactions between π-stacked Ni(ii)–thiazyl complexes
作者:Elisabeth M. Fatila、Rodolphe Clérac、Michael Jennings、Kathryn E. Preuss
DOI:10.1039/c3cc45605f
日期:——
The coordination complex of Ni(hfac)2 (hfac = 1,1,1,5,5,5-hexafluoroacetylacetonato) and the 4-(benzoxazol-2â²-yl)-1,2,3,5-dithiadiazolyl (boaDTDA) neutral radical Ï-stacks in a one-dimensional âstaircaseâ arrangement. This particular packing aligns regions of α and β spin densities on neighbouring NiII(hfac)2(boaDTDA) molecules. This complex exemplifies a McConnell I type mechanism, giving rise to intermolecular ferromagnetic exchange observed for the first time between metalâthiazyl complexes.
Ni(hfac)2(hfac = 1,1,1,5,5,5-六氟乙酰丙酮)和 4-(苯并恶唑-2â²-基)-1,2,3,5-二硫二唑(boaDTDA)中性基的配位复合物以一维 "楼梯 "排列方式堆叠。这种特殊的堆积方式使相邻的 NiII(hfac)2(boaDTDA)分子上的δ和δ自旋密度区域对齐。这种复合物体现了麦康奈尔 I 型机制,首次在金属噻唑复合物之间观察到了分子间铁磁交换。
Ferromagnetic superexchange in a 1D –[LaIII–radical]– coordination polymer
作者:Elisabeth M. Fatila、Rodolphe Clérac、Mathieu Rouzières、Dmitriy V. Soldatov、Michael Jennings、Kathryn E. Preuss
DOI:10.1039/c3cc43267j
日期:——
The first coordination polymer of a bridging radical 1,2,3,5-dithiadiazolyl ligand is reported. Upon coordination with the La(hfac)3 fragment, the paramagnetic 4-(benzoxazol-2â²-yl)-1,2,3,5-dithiadiazolyl (boaDTDA) ligand forms a one-dimensional (1D) alternating â[La(hfac)3âboaDTDA]nâ polymer exhibiting ferromagnetic (FM) coupling between the radicals, mediated through the diamagnetic LaIII ion (hfac = 1,1,1,5,5,5-hexafluoroacetylacetonato).