Free Energy Change at 37 °C
Folding free energy changes for Watson-Crick helices are predicted using the equation:
ΔG°37 Watson-Crick = ΔG°37 intermolecular initiation + ΔG°37 AU end penalty (per AU end) + ΔG°37 symmetry (self-complementary duplexes) + Σ[ΔG°37 stacking]
where intermolecular initiation is applied for bimolecular structure formation, the AU end penalty is applied once per each AU pair at the end of a helix, the symmetry correction is applied to self-complementary duplexes, and the stacking term is a sum of sequence-dependent parameters over all base pair stacks. For helices of P uninterrupted basepairs, there are P-1 stacks of pairs.
A list of references is here.