Two new coordination polymers, [Ni(Hpdc)(bib)(H₂O)]_n (1) and {[Ni(bib)₃](ClO₄)₂}_n (2), were prepared by mixing Ni²⁺, 3, 5-pyrazoledicarboxylic acid (H₃pdc)/p-nitrobenzoic acid and 1, 4-bis(imidazol-1-ylmethyl) butane (bib) by a hydrothermal method, respectively. X-ray crystallography reveals a 2D network constructed by six-coordinated Ni (Ⅱ) centers, bib, and Hpdc^2- ligands in complex 1, while a 2D network is built by Ni (Ⅱ) and bib ligands in 2. Furthermore, the quantum-chemical calculations have been performed on'molecular fragments'extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.