Alkoxy-Bridged Dicopper(II) Cores Meet Tetracyanonickelate Linkers: Structural, Magnetic, and Theoretical Investigation of Cu/Ni Coordination Polymers.

ABSTRACT: Two heterometallic Cu(II)/Ni(II) coordination polymers, [Cu₂(Hbdea)₂Ni(CN)₄]_n (1) and [Cu₂(dmea)₂Ni(CN)₄]_n·nH₂O (2), were successfully self-assembled in water by reacting Cu(II) nitrate with H₂bdea (N-butyldiethanolamine) and Hdmea (N,N-dimethylethanolamine) in the presence of sodium hydroxide and [Ni(CN)₄]^2-. These new coordination polymers were investigated by single-crystal and powder X-ray diffraction and fully characterized by FT-IR spectroscopy, thermogravimetry, elemental analysis, variable-temperature magnetic susceptibility measurements, and theoretical DFT and CASSCF calculations. Despite differences in crystal systems, in both compounds, each dinuclear building block [Cu₂(μ-aminopolyalcoholate)₂]²⁺ is bridged by diamagnetic [Ni(CN)₄]^2- linkers, resulting in 1D (1) or 2D (2) metal-organic architectures. Experimental magnetic studies show that both compounds display strong antiferromagnetic coupling (J = -602.1 cm^-1 for 1 and -151 cm^-1 for 2) between Cu(II) ions within the dimers mediated by the μ-O-alkoxo bridges. These results are corroborated by the broken symmetry DFT studies, which also provide further insight into the electronic structures of copper dimeric units. By reporting a facile self-assembly synthetic protocol, this study can be a model to widen a still limited family of heterometallic Cu/Ni coordination polymer materials with different functional properties.

SUBMITTER: Costa IFM 

PROVIDER: S-EPMC11017569 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature