We performed Grand Canonical Monte Carlo (GCMC) simulations of ethylene and ethane adsorption in K-C2 dataset structures with RASPA v2.0.4 assuming a rigid framework. The UFF forcefield was used for the framework Lennard-Jones potentials with a 12.8 Å cutoff radius. We assumed both C2 adsorbates to be connected pseudoatoms (Supporting Information Table ). We ran 25,000 initialization cycles, followed by 50,000 equilibration cycles. We performed simulations at pressure points recorded in the corresponding experimental isotherm that were closest to 10, 20, 50, 70, and 101 kPa, all at 298 K.