Analysis of the structural and thermodynamic parameters of the hydrogen bond in complementary pairs of DNA and RNA bases

Abstract

Density functional methods involving the B3LYP functional and M062X, WB97XD, and B97D ones optimized for calculations of long-range interactions are used to carry out theoretical analysis of the structural and thermodynamic parameters of complementary adenine-thymine, adenine-uracil, and guanine-cytosine base pairs with hydrogen bonds. The calculated values of the structural and thermodynamic parameters are corrected according to the basis superposition error. The enthalpy factor is demonstrated to prevail over the entropy one during the formation of the guanine—cytosine complex, indicating that the equilibrium constant is of great importance. It is discussed whether the M062X, WB97XD, and B97D functionals can be applied to describe hydrogen-bonded systems.