Intra-basepair Parameters Buckle(°) -44.83 Open angle(°) -68.9 Propeller (°) 6.09 Stagger (Å) 0.21 Shear (Å) 3.28 Stretch (Å) 3.69

Basepair Geometry C1'-C1' Distance(Å) 9.70 C6-C8 Distance (Å) 9.35 Opening (°) 5.26 Glycosidic angle- 1 (°) 46.73 Glycosidic angle- 2 (°) 77.59

Quantum Chemical interaction energy = -11.37 Kcal/mol

(Ref: Unpublished data)

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