Intra-basepair Parameters Buckle(°) -5.69 Open angle(°) -1.00 Propeller (°) 0.85 Stagger (Å) 0.11 Shear (Å) 2.35 Stretch (Å) 2.80

Basepair Geometry C1'-C1' Distance(Å) 12.06 C6-C8 Distance (Å) 9.76 Opening (°) 165.46 Glycosidic angle- 1 (°) 18.84 Glycosidic angle- 2 (°) 30.12

Quantum Chemical interaction energy = -14.36 Kcal/mol

(Ref: Panigrahi et al., Unpublished data)

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