CO2 gas molecules significantly promote both the translational and rotational motions of the n-C4H10/CO2 mixture in ZIF-10. CO2 molecules exhibit strong hydrogen bonds with the imidazolate rings leading to weakened interactions between alkanes and ZIF-10. Furthermore, both the translational and rotational motions are small compared to other gases. Thus, there was selective adsorption toward CO2 molecules compared to alkanes .