A microporous and noninterpenetrated metal-organic framework [Cu-3(L)(2)(DABCO)(H2O)]center dot 15H(2)O center dot 9DMF (1) has been synthesized using two different ligands, [1,1':3',1 ''-terphenyl]-4,4 '',5'-tricarboxylic acid (H3L) and 1,4-diazabicyclo[2.2.2]octane (DABCO). As revealed by variable-temperature powder X-ray diffraction (VT-PXRD) measurements, N,N'-ditopic DABCO plays an important role for stabilization of the Cu-L framework. The three-dimensional framework of 1 exhibits high stability and excellent adsorption capacity for H-2 (54.3 mg g(-1) at 77 K and 20 bar), CO2 (871 mg g(-1) at 298 K and 20 bar), CH4 (116.7 mg g(-1), 99 cm(3) (STP) cm(-3) at 298 K and 20 bar), and n-pentane (686 mg g(-1) at 298 K and 1 bar). Interestingly, the excellent selectivity toward CO2 over N-2 at ambient temperature (273 and 298 K) and 1 bar makes complex 1 possess practical application in gas separation and purification.