Intra-basepair Parameters Buckle(°) -38.56 Open angle(°) -85.77 Propeller (°) 65.54 Stagger (Å) 4.82 Shear (Å) 3.30 Stretch (Å) 3.96

Basepair Geometry C1'-C1' Distance(Å) 6.99 C6-C8 Distance (Å) 7.81 Opening (°) 174.72 Glycosidic angle- 1 (°) 45.46 Glycosidic angle- 2 (°) 74.56

Quantum Chemical interaction energy = -3.46 Kcal/mol

(Ref: Panigrahi et.al ,Unpublished data)

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