Express-method of estimation of the acid strength of H-acids

A theoretical express-method estimating acid strength of H-acids through calculation by the classical quantum-chemical semi-empirical MNDO method in Duar and Teel parameterisation with minimisation of total energy of the molecular system by the Davidon-Fletcher-Powell method have been offered. The practical use of this method has been demonstrated by estimating the acid The strength of RnBF3-n. HF complexes (where is R = CH3 and C2H5)(.) The geometrical and electronic structures of these complexes have been obtained. It is established that irrespective of the ligand surrounding of the B atom, the RnBF3 . HF complexes have a rather high acid strength (pK(x) = -17.9divided by-14.9).