<p>The adsorption behavior of CO₂ and N₂ on zeolitic imidazolate frameworks (ZIF-8 and ZIF-67) is investigated using a statistical physics approach. Experimental adsorption isotherms are measured over a temperature range of 268–323&#xa0;K and pressures up to 3000&#xa0;kPa. To provide a detailed microscopic interpretation of the adsorption mechanism, an advanced model based on statistical physics (AMSP) is employed, enabling the determination of key adsorption parameters such as the number of gas molecules captured per site, adsorption site density, and total number of adsorbed layers. The results reveal that CO₂ exhibits significantly higher affinity for ZIFs compared to N₂, with maximum saturation adsorption capacities of 4.28 mmol g^− 1 for CO₂ on ZIF-8 and 5.13 mmol g^− 1 for CO₂ on ZIF-67, compared to 2.37 mmol g^− 1 and 3.09 mmol g^− 1 for N₂, respectively. Most of the adsorption sites capture more than one molecule, indicating a multimolecular adsorption mechanism, with the total number of adsorbed layers ranging from 1.55 to 4.43 depending on gas type, temperature, and adsorbent. The adsorption process is found to be physical and exothermic, with adsorption energies below 10&#xa0;kJ mol^− 1 and capacity decreasing by up to ~ 35% with increasing temperature. Thermodynamic analyses, including Gibbs free energy and internal energy calculations, confirmed the spontaneous nature of the adsorption process. These findings highlight the potential of ZIF-based materials for selective CO₂ capture and provide a quantitative molecular-level framework for optimizing adsorption processes.</p>