Stacking profiles were also used to better account for dispersion and Pauli repulsion energies. 10 unique base pair combinations were also used for these profiles. As shown in Figure , nucleobases were stacked at three distinct orientations (0 • , 120 • , and 240 • ). For similar base pairs (e.g. A:A, U:U, etc.), the 0 • orientation is obvious. For dissimilar pairs (e.g.