Structure of Co-crystals Formation from Imidazolium and Aromatic Ligands

In this study, two new co-crystals based on rigid imidazolium ligand(2,2’-((1,1’-biphenyl)-4,4’-diyl)bis(2H-imidazo[1,5-a]pyridine-4-ium) hexafluorophosphate(L)) and 4,4’-bipyridine(Bpy) and benzene(Ben), formulated as L(Bpy)0.5(co-crystal 1) and L(Ben)(co-crystal 2), were obtained. Crystal data for 1: P1 space group with a = 10.921(4), b = 16.998(6), c = 17.666(6), α = 95.720(7), β = 104.272(7), γ = 93.340(6)°, V = 3150.5(19) 3 and Z = 2; and crystal data for 2: monoclinic C2/m space group with a = 25.90(2), b = 9.631(9), c = 6.371(6), β = 95.26(2)°, V = 1583(2) 3 and Z = 2. Co-crystal 1 was dependent on hydrogen bonds and π...π stacking, while only hydrogen bonds are present in 2. Two new co-crystals were characterized by IR, NMR spectra, thermogravimetric and ultraviolet absorption analyses.