Intra-basepair Parameters Buckle(°) -0.43 Open angle(°) -47.41 Propeller (°) 2.54 Stagger (Å) -1.11 Shear (Å) 5.23 Stretch (Å) 6.56

Basepair Geometry C1'-C1' Distance(Å) 7.24 C6-C8 Distance (Å) 7.28 Opening (°) 1.50 Glycosidic angle- 1 (°) 123.75 Glycosidic angle- 2 (°) 58.53

Quantum Chemical interaction energy = -1.34 Kcal/mol

(Ref: Panigrahi et.al ,Unpublished data)

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