Anion-Dependent Cu(II) Coordination Polymers: Geometric, Magnetic and Luminescent Properties

A one-dimensional (1D) coordination polymer [Cu-2(bpba)(CH3COO)(4)] (1) and a two-dimensional (2D) coordination polymer [Cu(bpba)(2)(H2O)(NO3)](NO3)center dot 2H(2)O center dot MeOH (2) were synthesized by the reaction between Cu(CH3COO)(2)center dot H2O/Cu(NO3)(2)center dot 3H(2)O and bis(4-pyridyl)benzylamine (bpba). The Cu(II) ions of 1 and 2 have distorted-square pyramidal coordination with a paddle-wheel structure and an octahedral geometry, respectively. By coordinating the Cu(II) ions and bpba ligands, 1 and 2 formed zigzag 1D and puckered 2D coordination polymers, respectively. Polymer 1 exhibits strong emissions at 355 and 466 nm, whereas polymer 2 exhibits strong emissions only at 464 nm. The emissions are strongly dependent on the geometry of the Cu(II) ions linked by the bpba and anionic ligands. Polymer 1 exhibits a very strong antiferromagnetic interaction within the paddle-wheel dimer, whereas polymer 2 exhibits a very weak antiferromagnetic interaction through the bpba linkers and/or space.

Automated summary

A one-dimensional (1D) and a two-dimensional (2D) coordination polymer were synthesized by reacting Cu(CH3COO)(2)·H2O/Cu(NO3)(2)·3H2O with bis(4-pyridyl)benzylamine (bpba). The Cu(II) ions in the polymers have different coordination structures leading to distinct emission properties. The type of coordination geometry significantly affects the emission behaviors in the polymers.