Abstract: The mechanism of the dimerization reaction of silathioformaldehyde has been studied by using ab initio method at HF/6 31G * and MP2/6 31G * levels.All the geometries of the stationary points on the reaction path have been optimized with the Berny energy gradient technique.The intermediate complex and the transition state were characterized by vibration frequency analysis.The results show that this reaction proceeds via two steps:(1)two silathioformaldehyde molecules form an intermediate complex through ...