Intra-basepair Parameters Buckle(°) -51.52 Open angle(°) -35.74 Propeller (°) -17.82 Stagger (Å) -1.22 Shear (Å) 0.99 Stretch (Å) 4.16

Basepair Geometry C1'-C1' Distance(Å) 7.86 C6-C8 Distance (Å) 7.12 Opening (°) 21.68 Glycosidic angle- 1 (°) 28.13 Glycosidic angle- 2 (°) 110.68

Quantum Chemical interaction energy = -8.17 Kcal/mol

(Ref: Panigrahi et. al, Unpublished data)

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