Synthesis and Magnetic Properties of a Dimerized Trinuclear Ni String Complex, [Ni₆Cl₂(dpa)₈](I₅)₂·0.25I₂ (dpa^– = 2,2′-Dipyridylamide Anion)

Abstract

Metal string complexes, linearly aligned transition metal arrays coordinated with the multidentate organic ligands, have gained much attention both in unique electronic/structural properties and in potential applications as conductive molecular nanowires. Here we report on a dimerized Ni II trinuclear complex, [Ni 6 Cl 2 (dpa) 8 ](I 5 ) 2 • 0.25I 2 (dpa − = 2,2′-dipyridylamide anion). X-ray structural analysis revealed that two trinuclear moieties are bridged by a Cl anion to form a dimerized string structure. This is the first example of two Ni string complexes that are connected. In the electronic absorption and Raman spectra, characteristic absorption bands and a vibration mode based on the dimer string structure were observed. In the solid state, dimer complexes align in one dimension in an MMMXMMMX (M = metal, X = halogen) manner, leading to the intra-and interdimer antiferromagnetic interactions.

Synthesis, structure, and magnetism of a novel series of trinuclear nickel(ii) clusters

“…carbonyl oxygen, hydrazine nitrogen, phenolic oxygen, and pyridine nitrogen atoms, adopting a square-planar geometry NiN 2 O 2 coordination environment. The distances from the Ni(II) ion to the donor atoms are in the range of 1.81-1.94 Å, which indicates square-planar Ni(II) ions should be presented in a diamagnetic low-spin ground state (S = 0), [39][40][41] which was also confirmed by the magnetic studies of 1-4.…”

Magneto-structural studies on a number of doubly end-on cyanate and azide bridged dinuclear nickel(ii) complexes with {N3O} donor Schiff base ligands

“…Di-and poly-nuclear transition metal complexes with organic ligands have been widely studied because of their applications in various elds including bioinorganic chemistry and magnetic materials. [1][2][3][4][5][6][7] In such metal complexes, the paramagnetic centres are either bridged by endogenous bridges such as phenolate ion or exogenous bridging ligands viz. hydroxide, alkoxide, carboxylate and pseudohalide groups or by a combination of both.…”

An efficient transition-metal-free route to oligo-α-pyridylamines via fluoroarenes

“…Depending on the number of linked α-pyridylamido units and on the presence of additional coordinating groups at the ligand's termini, structurally authenticated EMACs range from tri-to undecanuclear [2]. Among parent amines, widely used are di(pyridin-2-yl)amine (Hdpa) [6][7][8][9] and N 2 ,N 6 -di(pyridin-2-yl)pyridine-2,6-diamine (H 2 tpda) [10], whose mono-and dianions act as tri-and pentanucleating ligands, respectively (Figure 1).…”