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

• Published in: Journal of physical chemistry. C Vol. 128; no. 14; pp. 6053 - 6064
• Main Authors: Costa, Inês F. M., Franco, Chris H. J., Nesterov, Dmytro S., André, Vânia, Pereira, Laura C. J., Kirillov, Alexander M.
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 11.04.2024
• Subjects: C: Physical Properties of Materials and Interfaces
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.3c08112

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.