Two novel nickel() and cobalt() metal-organic frameworks based on a rigid aromatic multicarboxylate ligand: syntheses, structural characterization and magnetic properties

• Published in: CrystEngComm 2016-01, Vol.18 (28), p.5386-5392
• Main Authors: Hu, Tuo-Ping, Xue, Zhi-Jia, Zheng, Bao-Hua, Wang, Xiao-Qing, Hao, Xue-Na, Song, You
• Format: Article
• Language: English
• Subjects: Ferromagnetism; Ligands; Metal ions; Metal-organic frameworks; Nickel; Orbitals; Symbols; Topology
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/c6ce00674d

Two novel metal-organic frameworks, formulated as [Ni 3 (qptc) 2 (H 2 O) 3 ]·3.5H 2 O·3Me 2 NH ( 1 ) and [Co 3 (qptc) 2 (H 2 O) 4 ]·5H 2 O ( 2 ) (H 4 qptc = 1,1′:4′,1′′:4′′,1′′′-quaterphenyl-2,4,2′′′,4′′′-tetracarboxylic acid), have been hydrothermally constructed based on a rigid aromatic multicarboxylate ligand. The single-crystal X-ray diffraction analysis shows that complex 1 crystallizes in the triclinic crystal system with space group P 1&cmb.macr; and possesses a 4,8-connected 3D open framework including trinuclear nickel Ni 3 SBUs, which belongs to an scu topology with the point symbols (4 16 ·6 12 ) and (4 4 ·6 2 ). Complex 2 belongs to the monoclinic crystal system with space group C 2/ c and exhibits a 3D framework containing Co 3 SBUs, which is a flu topology with the point symbols (4 12 ·6 12 ·8 4 ) and (4 6 ). Furthermore, the variable-temperature magnetic susceptibilities of complexes 1 and 2 have been investigated. Both complexes show weak ferromagnetic coupling between metal ions estimated by using a linear trinuclear model for 1 in the range of 2-300 K and the PHI program for 2 in the range of 20-300 K taking the orbital contribution into consideration. Two novel transition metal-organic frameworks based on a rigid aromatic tetracarboxylate ligand have been synthesized and investigated.