Increasing the simulation temperature counteracts the adsorption energy and leads to a higher mobility of the adsorbate. In the flexible simulations, however, the confining influence at low loadings is the framework. Raising the temperature therefore does not significantly affect the mobility of the guest. Only at higher loadings, when the MOF is already significantly opened, the mobility of the guest differs between simulation temperatures. At the maximum simulated loading of 22 molecules, neither temperature nor flexibility of the host play a significant role since the packing of CO2 is dense and liquid-like (meaning no pronounced preferential ordering). The experimental maximum loading is difficult to determine exactly. As shown by Bon et al., even after adsorption some parts of the MOF stay closed. By estimating the relative amount of closed MOF one can derive a theoretical maximum loading of 21.5 molecules per formula unit MOF. As this requires in situ XRD measurements, this is not commonly done. The maximum loadings of CO2 in DUT-8(Ni) published therefore differ quite significantly. From our previous simulations and the experimental results mentioned, we suggest that the maximum loading in experiments will be in the range of 18 to 22 molecules CO2 per formula unit MOF (i.e. 27.36 to 33.45 mmol/g). The simulated line Copyright 2021, Zenodo.