A robust and water-stable porous coordination polymer [Cd-(NDC)(0.5)(PCA)]center dot G(x) (1) (H2NDC = 2,6-napthalenedicarboxylic acid, HPCA = 4-pyridinecarboxylic acid, G = guest molecules) with new network topology has been synthesized solvothermally. The framework is 3D porous material and forms a 1D channel along the c-axis, with the channel dimensions similar to 9.48 X 7.83 angstrom(2). The compound has high selectivity in uptake of CO2 over other gases (H-2, O-2, Ar, N-2, and CH4). The framework is highly stable in presence of water vapor even at 60 degrees C. The high CO2 selectivity over other gases and water stability makes the compound promising candidate for industrial postcombustion gas separation application.