A Series of Ca(II) or Ba(II) Inorganic-Organic Hybrid Frameworks Based on Aromatic Polycarboxylate Ligands with the Inorganic M-O-M (M = Ca, Ba) Connectivity from 1D to 3D

Solvothermal reactions of Ca(NO3)(2) or Ba(NO3)(2) with aromatic carboxylate ligands afforded four new inorganic-organic hybrid frameworks, [Ca(PBDC)(H2O)(3)](n) (1), [Ca-(OBDC)(H2O)](n) (2), [Ba-5(OBDC)(4)(H2O)(2)(NO3)(2)](n) (3), and [Ba-3(BTC)(2)(H2O)(4)](n) (4) (H2PBDC = terephthalic acid, H2OBDC = phthalic acid, H3BTC = 1,3,5-benzenetricarboxylic acid). These compounds have been fully characterized by single crystal X-ray diffraction, powder X-ray diffraction, satisfactory elemental analysis, IR spectra, and TG analysis. X-ray analysis shows that compound 1 features a one-dimensional chain (ID) structure with the (IO0)-O-1 connectivity, both compound 2 and compound 3 feature a two-dimensional (2D) layer structure with the (IO1)-O-1 connectivity, (IO0)-O-2 connectivity, respectively, compound 4 features a three-dimensional (3D) framework with a rare (IO0)-O-3 connectivity. Thermal stabilities and luminescent properties of compounds 1-4 and NLO property of compound 4 have also been investigated.