Rotaxane-based ligands 2 and 3 were synthesized from the respective macrocyle as well as alkyne and azide axle precursors using an active template Cu-mediated alkyne-azide cycloaddition reaction and the corresponding Co II complexes prepared (see ESI). In contrast to [Co(1)](ClO4)2, the asymmetric units of the solid-state structures obtained by SCXRD of [Co(2)](ClO4)2 and [Co(3)](ClO4)2 contain two very similar structures (bond length RMSD = 0.007 and 0.002 Å respectively, Table ). The SCXRD geometry of [Co(2)](ClO4)2 agrees well with the HS de novo model (bond length RMSD = 0.02 Å, Table ), with similar π-Co and ππ interactions observed in both, confirming that the modelling captures these inter-component interactions with reasonable accuracy. Similarly, although the calculated and observed structures of [Co(3)](ClO4)2 differ to a greater degree (bond length RMSD = 0.17 Å, Table ), perhaps in part due to there being more disorder in the corresponding SCXRD structure (Figure , Table ), the modelling accurately predicts the observed weak but structurally important Co-O interaction. Both the de novo models of [Co(2)] 2+ and [Co(3)] 2+ (10.9 and 18 kJ/mol respectively) and models constructed from the SCXRD coordinates (46.0 and 11.8 kJ/mol respectively) suggest a larger HS-LS gap than in the case of [Co(1)] 2+ , consistent with a single geometry being observed in their SCXRD structures. Based on the agreement between de novo models of [Co(1-3)] 2+ and their SCXRD-derived structures, the predictable nature of the coordination environment provided by a mechanically chelating ligand, combined with the ability of simple computational model s to accurately capture weak, geometry distorting interactions, allows the structure of such complexes to be predicted with reasonable precision. Finally, we compared the computationally predicted values of D obtained for the de novo HS models of [Co(1-3)](ClO4)2 with the models derived from the corresponding SCXRD geometries (Table ). Excitingly, large negative values of D were predicted for all three complexes in both sets of models. Given that SCXRD-derived models are typically employed when rationalizing the observed magnetic behavior of SIMs, this suggests that the de novo modeling approach is sufficient to identify interlocked complexes with potential SIM behavior. Thus, we turned to the experimental evaluation of the magnetic properties of [Co(1-3)](ClO4)2.