N,N'-dimethylethylenediamine, or m2m, is a diamine that that has one amine group coordinatively bound to an OMS and one amine group dangling in the pore (Figure ). The singly-bound attachment generally gives this material more rotational freedom in the pore, making distinctions between its configuration somewhat blurrier than the tetramines we will discuss in the next section. In fact, there is evidence that there are multiple motifs that are energetically available at finite temperatures . However, as in Lee, et al., we take the 'true' ground state configuration to be the one in which the ethylene-based arm is parallel to the crystallographic ab-plane (Figure ). The alternate configuration is the one in which this ethylene arm is pointing in the direction of the crystallographic c-axis (Figure ). Table shows the difference in the binding energies for the ab and c motifs for m2m. Since there are only two motifs, we present the difference in the binding energies between the two configurations, both for a single amine and the fully-loaded pore of 6 amines, computed as described in Equations 1 and 2.