As discussed above, the adjacent 2D sheets in 4 stack in parallel to b-axis, forming 1D XCT790 occupied by guest water molecules that consolidate the framework by hydrogen bonding. The frameworks of 4 can maintain its porous framework after evacuation, as can be confirmed by TGA and PXRD measurements ( Appendix A). The desolvated solid with 19.8% free void volume can be employed as microporous material to adsorb gases as the reported literature . A further study was subsequently undertaken to investigate the gas adsorption property of the desolvated sample 4′. As shown in Fig. 5, N2 sorption isotherms of compound 4′ suggest only surface adsorption . Similarly, no H2 and Ar adsorption was observed in Fig. S4. The gas sorption isotherms shows the CO2 uptake of 32.21 cm3/g at 195 K and 1 atm equivalent to 0.83 CO2 molecules per formula unit of the solid 4′, and a little hysteresis was observed between the adsorption and desorption curves ( Fig. 5). The distinct difference of adsorption capacity among CO2 and N2, H2, Ar for 4′ must be mainly attribute to that the Quadrupole Moment of CO2 (−1.4×10−39 C m2) is the important factor that affect the distinct difference of adsorption capacity  and .