Structural variability and photoluminescence properties of four neoteric 3D Cd(II) coordination polymers based on semirigid Bis(Thiazolylbenzimidazole) and different types of carboxylic acid linkers

Abstract

Four Cd(II) coordination complexes, formulated as [Cd(dbim)0.5(H2oba)]n (1), [Cd(dbim)(m-H2ada)]n (2), [Cd2(dbim)(1,2,4-H3btc)1.5]n (3) and [Cd(dbim)(H2sdba)]n (4), (dbim = 1-(4-((2,5-dimethyl-3aH-benzo[d]imidazole-1(7aH)-yl)methyl)benzyl)-3a,7a-dihydro-2,5-dimethyl-1H-benzo[d]imidazole, H2oba = 4,4′-oxybis(benzoic acid), m-H2ada = 1,3-adamantanediacetic acid, 1,2,4-H3btc = 1,2,4-Benzenetricarboxylic acid, H2sdba = 4,4′-sulfonyldibenzoic acid), have been prepared by hydrothermal reactions. Complex 1 reveal a 2-fold interpenetrating 3D frameworks with (412·63)-pcu topology. 2 display a 3-fold interpenetrating 3D frameworks with 63-dia Diamond topology. 3 exhibit a (3,6)-connected 3D topology net with point symbol of (42·610·72·8)(42·6). 4 is a 3D framework with a point symbol of (65·8). The structural comparison of complexes 1–4 shows that the final frameworks can be tuned by various carboxylate coligands and dbim ligand with changeable conformations. Moreover, thermal stability and photoluminescent properties of complexes 1–4 have also been investigated.