Intra-basepair Parameters Buckle(°) -29.29 Open angle(°) -37.57 Propeller (°) -63.56 Stagger (Å) 0.46 Shear (Å) 2.82 Stretch (Å) 3.37

Basepair Geometry C1'-C1' Distance(Å) 8.07 C6-C8 Distance (Å) 8.07 Opening (°) 21.38 Glycosidic angle- 1 (°) 129.41 Glycosidic angle- 2 (°) 23.58

Quantum Chemical interaction energy = -6.36 Kcal/mol

(Ref: Panigrahi et al., Unpublished data)

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