Figure 2.

(a) A view of the minor-groove solvent-accessible surface of one duplex, together with a symmetry-related duplex whose terminal Ni²⁺-TMPy ligand is embedded into the minor groove of the first duplex. (b) A second view, now looking directly down the groove. The nickel atom is shown as a green sphere, and the carbon atoms of the TMPy molecule are shown in purple. (c) Detailed view of the nonbonded distances <3.5 Å (shown in green) between the Ni²⁺-TMPy molecule and the minor groove. The close distances between the minor groove and the “carrier” duplex (colored blue) are also shown in cyan.