The solvothermal reactions of 1,4-bezenedicarboxylic acid (H₂BDC) or azobenzene-4,4′-dicarboxylic acid (H₂ABD) with zinc ions/clusters lead to the formation of four crystalline materials. All of these compounds were characterized by x-ray diffraction, optical microscopy, thermo-gravimetric analysis and nitrogen adsorption. Block-shaped crystals (BZ1) with various shapes and sizes were obtained at H₂BDC:Zn mole ratio of 1:1 and H₂BDC concentration of 0.1 M. At more dilute H₂BDC concentration of 0.01 M and H₂BDC:Zn mole ratio of 1 : 4, the reaction product was cubic crystals (BZ2) with a size of 250 μm. In the H₂ABD system, flat-plate-like crystals (AZ1) were obtained at H₂ABD:Zn mole ratio of 1 : 1 and H₂ABD concentration of 0.01 M. Meanwhile, thick-block-like crystals (AZ2) were formed at the same H₂ABD:Zn mole ratio but at 0.004 M H₂ABD. The Langmuir surface area (S_Lang) of the materials was remarkable, enhanced by diluting the reaction solution. For the compounds synthesized in N,N′-dimethylformamide (DMF), S_Lang increased from 304.6 m² g⁻¹ for BZ1 to 2631 m² g⁻¹ for BZ2 and from 475.8 m² g⁻¹ for AZ1 to 3428 m² g⁻¹ for AZ2. Meanwhile, BZ2 synthesized in N,N′-diethylformamide (BZ2/DEF) got the highest S_Lang of 4330 m² g⁻¹. Both AZ2 and BZ2 materials were stable up to 400 °C.