Relationship between stability and dimerization ability of silylenes

Isodesmic reaction energies and dimerization energies were calculated for several silylenes using B3LYP/6-31G(D) and MP2/6-311+G(2D) quantum chemical methods. Two different dimerization routes, the disilene formation and the four-membered bridge structure, were considered. The dimerization energy for disilene formation correlates excellently with the stabilization energy and the singlet–triplet energy separation of the silylenes. No correlation, however, has been found between the dimerization energy of the bridged dimer formation and the isodesmic reaction energy or the singlet–triplet energy separation of silylenes.