Quantum mechanical studies on the effect of ions at phosphate and sugar groups of DNA

Many studies have demonstrated the interaction of cation with the polyanionic regions of DNA. Different quantum mechanical methods are used to analyze the ion affinities around phosphate sugar region. The proton affinities are found much larger than Na⁺ and Mg²⁺ affinities. Further, we find that in most cases the ions can interact with multiple atomic sites of sugar-phosphate group.