Figure 1. 3-21G Molecular structures. Bond lengths in A, angles in degrees. energy increases monotonically upon rotation from pyramidal to planar. In the more stable form with M= Si the two Si-Si distances are very similar to those in disilane at a comparable level of theory, 2 with the base bond being slightly longer than the internal bond. For M= C, the Si-C bond is slightly shorter than that in methylsilane, while the Si-Si bond is much shorter than ...
