No abstract

No abstract

Chiral 3D microporous lanthanide and tartrate-based MOFs with thermally induced modulation of magnetic/luminescence properties and chiroptical activity.

SMM behavior and intense photoluminescence are reported for eleven dinuclear and tetranuclear compounds.

No abstract

Herein, the synthesisa nd study of bifunctional coordination polymers (CPs) with both magnetica nd photoluminescence properties, derivedfrom ah eterometallice nvironment, are reported.A sastarting point, three isostructural monometallicC Ps with the formula [M(m-2ani) 2 ] n (M II = Mn (1 Mn), Co (3 Co)a nd Ni (4 Ni); 2ani = 2-aminonicotinate), crystallise as chiral 2D-layered structures stacked by means of supramolecular interactions. These compounds show high thermals tabilityi nt he solid state (above3 50 8C), despite which, in aqueous solution,c ompound 1 Mn is shown to partially transform into an ovel 1D chain CP with the formula [Mn(2ani) 2 (m-H 2 O) 2 ] n (2 Mn). As tudy of the direct current (dc) magnetic properties of 1 Mn , 3 Co and 4 Ni revealsaspin-canted structure derived from antisymmetric antiferromagnetic weak exchanges along the chiral network (as confirmed by DFT calculations) and magnetic anisotropy of the ions, in such aw ay that long-range ordering is observed with variable magnitude for the spin carriers.M oreover,c ompounds 3 Co and 4 Ni show no frequency-dependent alternating current (ac)s usceptibilityc urvesu nder zero dc field;t his is characteristic behaviour of ag lassy state that may be partially supressed for 3 Co by applyinga ne xternal dc field. To overcome long-rangem agnetic ordering,C o II ions are diluted in ad iamagnetic Zn II-based matrix, which enables single-molecule magnet behaviour.I nterestingly,t his strategy allows a bifunctional Co x Zn 1Àx 2ani material, whichi si mbuedw ith a strongp hotoluminescent emitting capacity,a sc haracterised by an intenseb lue light followed by ag reen afterglow,t o be obtained.

A family of Mn(II)Ln(III) dinuclear and tetranuclear complexes (Ln = Gd and Dy) has been prepared from the compartmental ligands N,N’-dimethyl-N,N’-bis(2-hydroxy-3-formyl-5-bromobenzyl)ethylenediamine (H2L1) and N,N’,N”-trimethyl-N,N”-bis(2-hydroxy-3-methoxy-5-methylbenzyl)diethylenetriamine (H2L2). The Mn(II)Gd(III) complexes exhibit antiferromagnetic...

Five new compounds are reported herein starting from 2-hydroxy-6-methylnicotinic acid (H2h6mnic) and first-row transition metal ions, although H2h6mnic shows a prototropy in solution to lead to the 6-methyl-2-oxonicotinate (6m2onic) ligand...