Three coordination polymers (CPs), [Ni1.5(L)(bipy)2(H2O)3]n(1), [Zn(L)(Hbipy) (H2O)]n⋅2n(H2O) (2) and [Cu(bipy)2(H2O)2]n⋅2n(H2L)⋅ 3nH2O (3) (NaH2L=5‐sulfoisophthalic monosodium salt, bipy=4,4′‐bipyridine) have been synthesized by solvothermal methods. They were characterized by X‐ray single crystal diffraction, elemental and thermogravimetric analyses. Introduction of the auxiliary N‐donor ligand (bipy) can lead to three Ni(II), Zn(II) and Cu(II) CPs with three‐dimensional (3D) 4‐connected network of the point symbol of (75⋅9), one‐dimensional (1D) ladder and two‐dimensional (2D) lattice frameworks, respectively. Compound 1 is racemic, whose topological structure can be divided into left‐handed and right‐handed helices. The fluorescence emission peaks of compounds 1–3 are located at 416 nm, 412 nm and 455 nm, respectively, which may be attributed to the ligand to metal charge transfers. Variable‐temperature magnetic susceptibility measurements can reveal that there are ferromagnetic and antiferromagnetic exchange interactions between the neighboring spins in compounds 1 and 3, respectively, and compound 2 is a diamagnetism system. Compound 1 shows the second‐harmonic generation (SHG) response that is 4 times those of potassium dihydrogen phosphate (KDP).

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Two new isomorphic and heterogeneous coordination polymers (CPs), namely {[RE (L) (H2O) 2] · (Hbipy) · H2O} n (RE = Yb(1), Y(2), Na2H2L = 4,5-dihydroxy-1,3-benzenedisulfonic acid disodium salt, bipy = 2,2′-bipyridine) have been synthesized by hydrothermal methods and structurally characterized by elemental analyses, power X-ray diffraction (PXRD) and single crystal X-ray diffraction. Compounds 1 and 2 feature one-dimensional (1D) wavy ladder-like chain structures, which are further connected by hydrogen bonds from water molecules to result in two-dimensional (2D) layered structures. The 1H-protonated bipy molecules act as uncoordinated cations, leading to valences of zero in compounds 1 and 2. Compounds 1 and 2 emit luminescence at 382 nm and 372 nm in the ultraviolet regions, respectively. The luminescent emissions originate from the typical ligand-centered (n–π* and π–π*) transitions. In addition, compound 1 has characteristic near-infrared emission of ytterbium ion at 964 nm.

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