Intra-basepair Parameters Buckle(°) 10.54 Open angle(°) -10.96 Propeller (°) 36.74 Stagger (Å) -0.37 Shear (Å) -0.46 Stretch (Å) 2.99

Basepair Geometry C1'-C1' Distance(Å) 7.29 C6-C8 Distance (Å) 8.26 Opening (°) 89.73 Glycosidic angle- 1 (°) 107.51 Glycosidic angle- 2 (°) 26.24

Quantum Chemical interaction energy = -9.82 Kcal/mol

(Ref: Panigrahi et al., Unpublished data)

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