Calculations of isotope effects by means of EC

Possibilities of computers for the calculation of isotope effects in organic chemistry, are considered in detail. It is shown that such operations as the selection of coordinates, selection of the methods of solving secular oscillation equation, selection of parameters are necessary for operating using computers. The selection of parameters is reduced to determining the length of bonds and valent angles, force constants, oscillation frequencies along reaction cooridnate. Three-centre model of hydrogen transfer, some important general principles of plotting a mathematical model and its computer processing are shown. A complete model of isotope effects in reactions of hydrogen transfer is compared with contracted models with certain simplifications. The plotting of the model of possible isotope effects in bimolecular splitting-off reaction is considered, as well as models based on quantum calculations