A model for the helix–coil transition of DNA

The helix–coil phase transition of DNA is studied through a model equivalent to the one used in the theory of superconductivity. A distribution function for the excitations analogous to the usual Fermi function is obtained which depends on the parameter T₀, the maximum temperature at which all pairs of bases are bonded. The expression for the number of unbonded pairs of bases depends only on the two parameters, T₀ and T_c (critical temperature).