Through theoretical calculations of C NMR line widths from MD simulations, we have disproven a possible reason for the difference in residual chemical shift anisotropy of the 13 C NMR signal of carbon dioxide in rigid and flexible forms of DUT-8(Ni). The lower anisotropy (narrower signal) of CO2 in the rigid DUT-8(Ni) samples can, according to our simulations, not be explained by an ordering force of the framework on the carbon dioxide molecules. The flexibility of the framework does not influence the orientation of the guest molecules at full loading and can therefore not be the cause of the broader signal (higher degree of order) in the flexible, larger crystallites. The methods and tools used throughout this work are not specific to the investigated MOF and can therefore be used to study confinement of CO2 in other materials. By implementing a fast and easy to use algorithm, we enable a wide community to perform direct comparisons between NMR measurements and MD simulation.