Grand canonical Monte Carlo simulations
To have a better insight into the excellent
C2H2 separation ability of
Zn2(bpy)(btec), GCMC simulations were performed to
structurally elucidate how C2H2molecules are adsorbed in this MOF.35,37,38 The
calculated binding sites of C2H2 are
shown in Figure 6. The C2H2 molecules
are preferentially located in the pore cavities between the layers of
Zn2(bpy)(btec). The C–H···O hydrogen bonds of each
C2H2 molecule interacts with two oxygen
molecule with a distance of 2.2~2.33 Å, which are much
shorter than the sum of the van der Waals radii of oxygen (1.52 Å) and
hydrogen (1.20 Å) atoms, indicating a relatively strong interaction.