Two-dimensional random walk and critical behavior of double-strand DNA

摘要

The phase behavior in a double-strand homopolynucleotide is considered. The relative distance between the corresponding monomers of two polymer chains is modeled by the two-dimensional random walk on the square lattice. Returns of the random walk to the origin describe the formation of base pairs between the complementary units. We obtain a completely denatured state below the finite temperature T_c. It was shown that T_c is the point of the infinite-order phase transition. The specific behavior of the order parameter, free energy and correlation functions has been addressed.