An underexplored reaction of pyrazine (rigid and linear) and succinic acid (flexible) with Co­(NO3)2·6H2O afforded four new coordination polymers (CPs): [Co­(H2O)­(pyz)­(suc)] (1), [Co­(H2O)2(pyz)­(suc)] (2), [Co­(H2O)4(pyz)]­(suc) (3) and [Co2(H2O)2(pyz)­(suc)2] (4), as well as [Co­(HCO2)2(pyz)] (5) being lately reported along with well-known 6 and 7. The CPs were obtained as stable crystalline materials and characterized by conventional solid-state techniques, including X-ray crystallography. Hydrothermally produced compounds 1 and 2 were both 3D CPs. While 3 and 4 obtained under ambient/solvothermal conditions in DMSO generated 1D and 3D structures, 5 isolated from DMF under solvothermal conditions had a 3D structure. The topologies of the coordination polymers 1–7 were described by underlying nets 3D 5-c fet, 3D 4-c cds, 1D 2-c 2C1, 3D 5-c bnn, 3D 6-c rob, 1D 2-c 2C1, and 3D 6-c pcu, respectively. The plot of χM –1 versus T was essentially linear in the entire temperature range following the Curie–Weiss law with a Curie constant (C) of 2.525 and a negative Weiss constant (ϕ) of −46.24 K, suggesting weak antiferromagnetic (AF) exchange interactions. CO2 and N2 adsorption studies of 1–5 featured type III isotherms. 1 was found to show remarkably higher quenching efficiencies for nitrophenols (η = 98% for o-NP) over other NACs. The Stern–Volmer plot exhibited deviation in linearity with K sv values about 200 times greater than that for the simplest nitroaromatic compound (NB), signifying its exclusive quenching ability toward 1. The LOD for p-NP addition to 1 was found to be 0.995 ppm.

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Hydrothermal synthesis, crystal structure and properties of a new heterometallic coordination polymer [(VO(terpy))4(MoO4)2(Mo8O26)]·2H2O (1) (terpy = 2,2′;6′,2″-terpyridine) are reported. Compound 1 contains two crystallographically unique vanadium(IV) atoms, bonded to a terminal oxido ligand and further coordinated to a terpy ligand. The three N atoms of terpy occupy the meridional sites of a distorted {VN3O3} octahedron. A γ-octamolybdate (Mo8O26)4– located on an inversion centre and a tetraoxidomolybdate (MoO4)2– function as bridging ligands. The μ3-bridging tridentate binding of (MoO4)2– leads to the formation of a {V4Mo2O12}4+ cationic unit consisting of an eight-membered heterometallic {Mo2V2O4} ring with protruding oxidovanadium handles. A pair of {V4Mo2O12}4+ units are bridged by the centrosymmetric (Mo8O26)4– ligand, resulting in the formation of an infinite chain of alternating {V4Mo2O12}4+ cations and (Mo8O26)4– anions.

A Co(II) coordination polymer [Co(suc)(bpm)] ⋅ 2H2O (1) built from succinate (suc) and bipyrimidine (bpm) is synthesized hydrothermally and characterized by different methods. It crystallizes in a monoclinic space group P21/n with an intriguing 3D polymeric architecture. The weak antiferromagnetic (AF) exchange interactions were evinced by Curie Constant (C)=1.803 cm3mol−1K and a negative Weiss constant (φ)=−30.163 K. Type VI adsorption isotherm behavior of 1 at 77 K revealed its non‐porous property. Compound 1 was investigated and successfully utilized as an additive in lowering the decomposition temperature of ammonium nitrate (AN) based fuels as demonstrated from TG and DSC experiments performed in nitrogen atmosphere.