Qspr Modeling Organic Compounds Gibb's Free Energy by Weighting of Nearest Neighboring Codes
Abstract
We examine the encoding of chemical structure of organic compounds by abeled ydrogen - illed raphs (LHFGs). uantitative tructure-roperty elationships (QSPR) for a representative set of 150 organic molecules have been derived by means of the optimization of correlation weights of local invariants of the LHFGs. We have tested as local invariants Morgan extended connectivity of zero- and first order, numbers of path of length 2 (P2) and valence shells of distance of 2 (S2) associated with each atom in the molecular structure, and the Nearest Neighboring Codes (NNC). The best statistical characteristics for the Gibbs free energy has been obtained for the NNC weighting. Statistical parameters corresponding to this model are the following n = 100, r= 0.9974, s = 5.136 kJ/mol, F = 38319 (training set); n = 50, r = 0.9990, s = 3.405 kJ/mol, F = 48717 (test set). Some possible further developments are pointed out.