Intra-basepair Parameters Buckle(°) -11.27 Open angle(°) 22.62 Propeller (°) -0.47 Stagger (Å) -0.01 Shear (Å) 2.39 Stretch (Å) 2.60

Basepair Geometry C1'-C1' Distance(Å) 7.61 C6-C8 Distance (Å) 5.87 Opening (°) 41.90 Glycosidic angle- 1 (°) 81.78 Glycosidic angle- 2 (°) 54.48

Quantum Chemical interaction energy = -8.75 Kcal/mol

(Ref: Panigrahi et. al, Unpublished data)