Intra-basepair Parameters Buckle(°) 7.83 Open angle(°) -12.63 Propeller (°) 10.49 Stagger (Å) 0.27 Shear (Å) -0.03 Stretch (Å) 2.85

Basepair Geometry C1'-C1' Distance(Å) 10.93 C6-C8 Distance (Å) 7.33 Opening (°) 143.51 Glycosidic angle- 1(°) 39.31 Glycosidic angle- 2(°) 25.31

Quantum Chemical interaction energy = -9.84 Kcal/mol

(Ref: Panigrahi et. al, Unpublished data)

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