Syntheses, Structures, and Magnetic Properties of Three Novel Metal−Malate−Bipyridine Coordination Polymers with Layered and Pillared Topology

• Published in: Crystal growth & design 2006-05, Vol.6 (5), p.1101-1106
• Main Authors: Duan, Li-Mei, Xie, Feng-Tong, Chen, Xiao-Yan, Chen, Yan, Lu, Yu-Kun, Cheng, Peng, Xu, Ji-Qing
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Growth from solutions; Materials science; Methods of crystal growth; physics of crystal growth; Organic compounds; Organometalloidal and organometallic compounds; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids
• ISSN: 1528-7483; 1528-7505
• DOI: 10.1021/cg050382q

The combination of metal ions with malic acid (hydroxybutane diacid) and 4,4‘-bipyridine ligands under hydro(solvo)thermal conditions has resulted in the formation of three novel coordination polymers, {[M(C4H4O5)(bipy)0.5]·H2O} n (M = CoII (1), NiII (2), 0.3CoII + 0.7NiII (3); C4H4O5 2- = malate dianion, bipy = 4,4‘-bipyridine). The metal ions were interconnected by α- and β-carboxylates of malate to produce infinite [M(C4H4O5)] n layers, which were further pillared by bridging bipy molecules to form a 3D network. The μ3-malate ligand exhibits a pentadentate coordination mode, with all of the five oxygen atoms participating in the coordination. The magnetic pathways of three compounds are through M−O−C−O−M with nonplanar skew-skew conformations; compound 1 shows antiferromagnetic interactions, while 2 is ferromagnetic, due to different electronic configurations of the metal ions.