Intra-basepair Parameters Buckle(°) 56.44 Open angle(°) -55.07 Propeller (°) 4.58 Stagger (Å) -0.07 Shear (Å) -3.03 Stretch (Å) 3.42

Basepair Geometry C1'-C1' Distance(Å) 7.16 C6-C8 Distance (Å) 7.81 Opening (°) 21.07 Glycosidic angle- 1 (°) 93.79 Glycosidic angle- 2 (°) 52.72

Quantum Chemical interaction energy = -5.35 Kcal/mol

(Ref: Unpublished data)

Intra-basepair parameters and basepair geometry are calculated by NUPARM.