A 3-D cobalt(II)-coordination polymer with mixed-connected network topology constructed from 4-pyridin-3-yl-benzoic acid

Abstract

A new coordination polymer, [Co₂(μ-H₂O)(4,3-pybz)₄] _n (1), has been hydrothermally synthesized from Co(NO₃)₂ · 6H₂O and an unsymmetrical 4-pyridin-3-yl-benzoic acid (4,3-Hpybz), which is characterized by IR, elemental analysis, thermogravimetric analysis, and single crystal X-ray diffraction. This compound crystallizes in monoclinic, space group C2/c with a = 11.876(3) Å, b = 15.462(3) Å, c = 21.545(4) Å, β = 94.873(5)°, V = 3942.0(15) ų, Z = 4, Dc = 1.565 g cm⁻³, F(000) = 1904, GOF = 1.025, μ = 0.910 mm⁻¹, R ₁ = 0.0456, wR ₂ = 0.0983. Compound 1 shows a 3-D (3,6)-connected coordination framework with (3.4.5)(3².4⁴.5⁵.6².7²) topology, in which cobalt is a six-connected node, and the 4,3-Hpybz ligands serve as two-connected spacers and three-connected nodes. In addition, the magnetic and thermal properties of 1 have also been investigated.

Keywords:

• Cobalt(II) compound
• Crystal structures
• Topology
• Magnetic properties

Acknowledgments

This project was supported by the Nature Scientific Foundation of the Shaanxi Province of China (No. SJ08B11), the Key Project of Key Laboratory of Shaanxi Province (No. 08JZ82), the Natural Scientific Research Foundation of Shaanxi Provincial Education Office of China (Nos. 07JK435, 08JK490, 09JK816, 09JK826, and 09JK815).