Structural diversity and magnetic properties of six cobalt coordination polymers based on 2,2′-phosphinico-dibenzoate ligand

Abstract

Six novel Co(ii) coordination polymers, namely, [CoL(OH)(HO)]·10.5HO (1), [CoL(3-abpt)]·4HO (2), [CoL(4-azpy)(HO)(EtOH)] (3), [CoL(4,4'-bipy)(HO)(MeCN)] (4), [CoL(4,4'-bipy)] (5), and [CoL(OH)(ina)(HO)] (6) (HL = 2,2'-phosphinico-dibenzoic acid, 3-abpt = 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole, 4-azpy = 4,4'-azobispyridine, 4,4'-bipy = 4,4'-bipyridine, Hina = isonicotinic acid), have been hydrothermally synthesized and their magnetic properties have been characterized. The L anion displays six types of coordination modes in the compounds. Compound 1 exhibits a novel 1D ladder-like structure, which consists of non-centrosymmetric Co units. Compounds 2-4 comprise 2D networks assembled from CoL chains and N-heterocyclic linkers. Compound 5 comprises a 3D framework built from six neighboring parallel CoL ladders bridged by 4,4'-bipy linkers. Compound 6 features a 3D framework that exhibits pcu topology with the Schläfli symbol of (4·6) using a pentanuclear [Co(OH)] cluster as the node. Variable-temperature magnetic susceptibility studies indicate that the six coordination polymers exhibit remarkable magnetic behavior such as spin-canted antiferromagnetism and spin glass, which were found to coexist in compound 6.

Nonenzymatic Glucose Sensing and Magnetic Property Based On the Composite Formed by Encapsulating Ag Nanoparticles in Cluster-Based Co-MOF

“…The large Co–O–Co angles and long Co···Co separations for Co1 and Co3 atoms and for Co2 and Co3 atoms cause the antiferromagnetic interactions between these two pairs of Co­(II) centers, while the small Co–O–Co angles and short Co···Co separations determine the ferromagnetic exchanges between Co1 and Co2 atoms (Figure S10). − Therefore, the cluster and framework display an overall antiferromagnetic behavior, and the similar magnetic properties were also reported in a cluster-based complex, [Co II 5 (N 3 ) 2 ( N - n -bda) 2 (bae) 2 (bza·SMe) 2 ]·1.5H 2 O …”

A Co-Crystallised Cobalt(II) Cluster of Pyridinedicarboxylic Acid (PDC) as a Luminescent Material for Selective Sensing of Methanol

“…Only one hydrogen atom was observed and modelled for water ligand O11W (Fig. 1) [24]. Also, the bond angles around the Co 2+ ions in the complexes are in the range 72.1(5) to 180.00 (11) which is in good agreement with literature [25].…”

Crystal structure of bis(hydroxydi(pyridin-2-yl)methanolato-κ3 N,N′O)cobalt(III) 7,7,8,8-tetracyanoquinodimethane, C34H22CoN8O4

“…Rational design and construction of cobalt complexes has garnered remarkable attention in the field of molecular materials owing to their potential applications in biochemistry, catalysis, electrochemistry, hydrogen production and magnetism [3][4][5].…”