Intra-basepair Parameters Buckle(°) -85.99 Open angle(°) -25.43 Propeller (°) -17.14 Stagger (Å) -1.70 Shear (Å) 0.99 Stretch (Å) 2.94

Basepair Geometry C1'-C1' Distance(Å) 6.96 C6-C8 Distance (Å) 5.14 Opening (°) 77.98 Glycosidic angle- 1 (°) 30.21 Glycosidic angle- 2 (°) 66.38

Quantum Chemical interaction energy = -2.48 Kcal/mol

(Ref: Panigrahi et.al ,Unpublished data)

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