QSPR modeling of complex stability by optimization of correlation weights of the hydrogen bond index and the local graph invariants

The hydrogen bond index (HBI) is the global invariant of a molecular graph and equals the number of vertices representing hydrogen and nitrogen atoms. This index was considered a measure of the capability of a complex to form hydrogen bonds. Optimization of the correlation weights of the HBI and local graph invariants was used for the QSPR modeling of the stability of 110 biometal M²⁺ complexes with α-amino acids and phosphate derivatives of adenosine. The statistical parameters of the best model are n = 55. r = 0.9921, s = 0.279, and F = 3328 (learning sample) and n = 55, r = 99.35, s = 0.248, and F = 4027 (control sample).