NEW APPROACH TO THE DETERMINATION OF MOLECULAR SPATIAL STRUCTURE BASED ON THE USE OF SPECTRA AND COMPUTERS

It has been demonstrated that the problem of determination of molecular structure can be solved by consecutive applications of the methods of experimental and theoretical spectroscopy, quantum chemistry and computer analysis without the use of X-ray structural analysis, diffractometry, etc. The structural formula is first established with the help of the automatic structure identification system STREC from IR, Raman, UV, NMR and mass spectra. Then the computer constructs the spatial model of the molecule from the standard vector models of atoms. Geometric parameters are refined with the help of atom-atom potentials and quantum-chemical calculations. Final selection of the molecular configuration is made on the basis of comparison of calculated vibrational and electronic spectra (in the form of curves) with experimental spectra. © 1979.