Development of a method to accurately calculate the Dpb and quickly predict the strength of a chemical bond

Highlights: ► A method from new respect to characterize and measure the bond strength is proposed. ► We calculate the Dpb of a series of various bonds to justify our approach. ► A quite good linear relationship of the Dpb with the bond lengths for series of various bonds is shown. ► Take the prediction of strengths of C–H and N–H bonds for base pairs in DNA as a practical application of our method. - Abstract: A new approach to characterize and measure bond strength has been developed. First, we propose a method to accurately calculate the potential acting on an electron in a molecule (PAEM) at the saddle point along a chemical bond in situ, denoted by Dpb. Then, a direct method to quickly evaluate bond strength is established. We choose some familiar molecules as models for benchmarking this method. As a practical application, the Dpb of base pairs in DNA along C–H and N–H bonds are obtained for the first time. All results show that C7–H of A–T and C8–H of G–C are the relatively weak bonds that are the injured positions in DNA damage. The significance of this work is twofold: (i) A method is developed to calculate Dpb of various sizable molecules in situ quickly and accurately; (ii) This work demonstrates the feasibility to quickly predict the bond strength in macromolecules