Homo- and heterometallic coordination networks based on linear trinuclear Co(II) units: syntheses, structures and magnetic properties

作者：Huang Wun Jhih; Hsu Chia Ju; Tsai Shao Kang; He Hsiu Yi; Ding Jaw Jih; Hsu Ting Wei; Yang Chun Chuen^*; Chen Jhy Der

来源：RSC Advances, 2015, 5(30): 23374-23382.

DOI：10.1039/c5ra00728c

Two three-dimensional (3D) coordination networks, [Co-3(1,4-BDC) 3(L-1)](infinity) (L1 = N,N'-bis(3-pyridinyl)-1,4-benzenedicarboxamide; 1,4-H2BDC = 1,4-benzenedicarboxylic acid), 1, and [K2Co3(L-2) 4](infinity) (H2L2 = 5-acetamidoisophthalic acid), 2, have been synthesized by hydrothermal reactions and characterized by single crystal X-ray crystallography. Complex 1 consists of linear trinuclear Co(II) centers, which are linked by the 1,4-BDC- and L1 ligands to form a rare (1 + 3) self-catenated 3D net with the new (36,410,511,6) topology, and complex 2 reveals a 3p-3d heterometallic coordination network based on linear trinuclear Co(II) and dinuclear K(I) centers bridged by the mu(6)-L-2 ligands, forming a 4,4,8-connected trinodal net with the new (4(14).6(10).8(4))(4(2).6(4))(4(4).6(2)) topology. The linear trinuclear Co(II) centers in 1 adopt the square pyramidal-octahedral-square pyramidal geometries, whereas those in 2 are tetrahedral-octahedral-tetrahedral. Both of the complexes exhibit paramagnetism that is consistent with the Curie-Weiss law between 60 and 300 K. The effective magnetic moments (<mu(eff)>) of both complexes are larger than the estimated value of 6.71 mu(B)/f.u., revealing the spin-orbit couplings that are invoked by the different distorted geometries of the linear trinuclear Co(II) centers. The dinuclear K(I) centers in 2 weaken the magnetic coupling, and reduce the antiferromagnetic ordering at 6 K.

• 出版日期2015