From Table column 3, it can be observed that the ILD, in general, was modified for all TM-intercalated 2D COF materials with respect to the pure 2D COF (3.34 Å), due to the interaction between 2D COF layers and the TM atoms. Initially, we expected the ILD to increase proportional to the number of intercalated atoms; however, this was not the case. For structures with Cr, Ti, and V intercalants, we observe a trend where the TM-03 configuration has an equal or smaller ILD than TM-01 and TM-02 configurations. Even though TM-03 COFs have more atoms intercalated in the bilayer, their position at the centroid of benzene rings (instead of boroxine or triazine rings) reduces their ILD. This reduced distance indicates highly favorable binding between the TMs (Cr, Ti, and V) and benzene rings. On the other hand, structures intercalated with Cu atoms follow the expected proportional increase with the number of intercalated atoms, except for Cu-02 and Cu-03, which have the same ILD of 3.44 Å. A similar phenomenon occurs in Mn-intercalated structures, where Mn-03 (3.45 Å) presents very similar ILD as Mn-02 (3.44 Å). Furthermore, Fe-intercalated structures present an increasing ILD for Fe-01, Fe-02, and Fe-03 configurations; however, there is a decrease from Fe-03(3.46 Å) to Fe-04a (3.39 Å). The only difference between Fe-03 and Fe-04a configurations is an additional Fe atom intercalated at the centroid of boroxine rings; therefore, the decrease in ILD leads us to propose that Fe has a similar affinity to benzene, boroxine, and triazine rings. This is reflected in the binding energies, which are very similar for configurations Fe-03, Fe-04, and Fe-05. This behavior also occurs in Sc-03 and Sc-04a, where the ILD decreases by adding a TM at the centroid of boroxine rings. Interestingly, the Fe and Sc intercalation also have similar binding energy trends for the different concentrations intercalation patterns. On the other hand, Mn-and Ni-intercalations are the only groups that follow the initally-expected trend, where the ILD is proportional to an increasing number of intercalated atoms. Another interesting result is that the ILDs of configurations Co-01b (3.33 Å), Co-04a (3.33 Å), Cr-01b (3.28 Å), Cr-03 (3.11 Å), Cr-04b (3.17 Å), Fe-01a/b (3.28/3.27 Å), Ti-01b (3.29 Å), Ti-03 (3.26 Å), Ti-04b (3.32 Å), V-01a/b (3.31/3.28 Å), V-03 (3.21 Å), and V-04b (3.29 Å) are smaller than the ILD of the pristine structure, suggesting weaker steric repulsions and potentially indicating high affinity between TMs and COF layers for these configurations. Finally-in terms of intercalants moving in the xy plane-we observe that for most structures, the TMs tend to stay at or near the centroid of the rings. Cu, Ni, and Sc are the only outliers (see Figures , and S7 in the supplementary information). The Cu atoms at the centroid of benzene rings tend to drift toward triazine rings, and the Ni & Sc atoms drift toward boroxine rings.