Intra-basepair Parameters Buckle(°) -21.56 Open angle(°) 21.55 Propeller (°) -42.67 Stagger (Å) -1.04 Shear (Å) -0.20 Stretch (Å) 2.82

Basepair Geometry C1'-C1' Distance(Å) 7.28 C6-C8 Distance (Å) 8.15 Opening (°) 79.36 Glycosidic angle- 1 (°) 28.13 Glycosidic angle- 2 (°) 107.58

Quantum Chemical interaction energy =- 10.33 Kcal/mol

(Ref: Unpublished data))

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