Structural analysis and magnetic properties of the 2-D compounds [M(N3)2(bpa)]n (M = Mn, Co or Ni; bpa = 1,2-bis(4-pyridyl)ethane) †

Abstract

Isomorphous compounds exhibiting the general formula [M(N 3 ) 2 (bpa)] n (M = Mn II 1, Co II 2 or Ni II 3; bpa = 1,2bis(4-pyridyl)ethane) have been prepared and magnetostructurally characterised. X-Ray diffraction analysis revealed a 2-D arrangement of octahedrally co-ordinated metal cations where di-µ-(1,3)-N 3 -bridged metallic chains are connected through bpa ligands. IR and UV-VIS spectra were consistent with this structural characterisation. Magnetic analysis carried out by means of ESR spectroscopy and susceptibility measurements indicated that the three compounds are antiferromagnetic, J values being Ϫ5.7, Ϫ14.0 and Ϫ80 cm Ϫ1 for 1, 2 and 3, respectively.

Weak Ferromagnetism Caused by a 2D Effect in Two New Cobalt(II)– and Nickel(II)–1,2‐Bis(4‐pyridyl)ethane (bpa) Polynuclear Compounds

“…As a result, bpa is characterised by a high capability to be incorporated into the structural framework, as illustrated by the increasing amount of bpa polymers reported during the last years. [1] Our previous works with bpa concern four families of polymers where this ligand is combined with pseudohalides {azido (N 3 ), [2] dicyanamido [N(CN) 2 ], [3] thiocyanato (NCS) [4] and cyanato (NCO) [5] }. The use of these ligands focuses on the generation of significant magnetic interactions through hydrogen bonds to give a global 2D network.…”

“…It is worth mentioning that few examples of M-L-bpa [L = NCS [6] and N(CN) 2 [3,7] ] can be found in the literature. For L = N 3 and NCO the [M(N 3 ) 2 (bpa)] (M = Mn, Fe, Co and Ni) [2,8] and [M(NCO) 2 (bpa) 2 ]·bpa (M = Mn and Co) [5] compounds have been characterised to date.…”

“…In this context, this paper reports on the synthesis and magnetostructural characterisation of the polynuclear compounds [M(NCO) 2 (bpa) 2 ] n [M = Co (1) and Ni (2)]. These isomorphous compounds exhibit M-(gauche-bpa) 2 -M chains that are connected through hydrogen bonds to give a 2D global network.…”

“…These isomorphous compounds exhibit M-(gauche-bpa) 2 -M chains that are connected through hydrogen bonds to give a 2D global network. The metal ions are octahedrally coordinated, and this arrangement gives rise to a 2D effect showing a ferromagnetic component.…”

New Polymeric Manganese Azide Derivatives with Quinazoline

“…[1] The versatility of this ligand is a direct consequence of its ability to act as a bridge in a large variety of coordination modes. For example, it is able to link two cations [in either end-to-end (EE) [2][3][4] or end-on (EO) [3,5] modes], three cations in the more exotic µ 1,1,1 or µ 1,1,3 modes, [4] or act as a bridge between four metallic centres in the rare examples of µ 1,1,1,1 and µ 1,1,3,3 modes. [5] The simultaneous presence of more than one of these coordination modes in the same compound is not rare, and this increases the number of possible topologies.…”