Intra-basepair Parameters Buckle(°) -75.26 Open angle(°) -27.85 Propeller (°) -31.57 Stagger (Å) -1.1 Shear (Å) 0.59 Stretch (Å) 4.29

Basepair Geometry C1'-C1' Distance(Å) 9.28 C6-C8 Distance (Å) 9.89 Opening (°) 99.90 Glycosidic angle- 1 (°) 45.28 Glycosidic angle- 2 (°) 90.11

Quantum Chemical interaction energy = -4.31 Kcal/mol

(Ref: Panigrahi wt. al et al., Unpublished data )

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