Intra-basepair Parameters Buckle(°) 1.35 Open angle(°) -5.62 Propeller (°) 30.25 Stagger (Å) 0.18 Shear (Å) 0.04 Stretch (Å) 2.98

Basepair Geometry C1'-C1' Distance(Å) 8.46 C6-C8 Distance (Å) 10.38 Opening (°) 53.94 Glycosidic angle- 1(°) 121.77 Glycosidic angle- 2(°) 57.57

Quantum Chemical interaction energy = -5.41 Kcal/mol

(Ref: Panigrahi et. al, Unpublished data)

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