Mechanisms of reactions between >Si=O groups and CO2, N2O, and HC≡CH molecules : An experimental and quantum chemical study

IR spectroscopy and quantum chemical calculations are used to study the directions and kinetics of reactions between silanone groups (≡Si-O)2Si=O and CO2, N2O, and acetylene molecules. IR bands are assigned on the basis of the calculation of vibrational spectra of model low-molecular systems. Quantum chemical methods are used to obtain the data on the shapes of potential energy surfaces of these systems (intermolecular complexes and transition states). These data are used to interpret kinetic data. The silanone group is inclined to the formation of relatively stable (~10 kcal/mol) intramolecular complexes with CO2, N2O, and acetylene molecules. Their geometries and electronic structures are determined.