Knowledge Bank

An investigation of the nature of ``group vibrations'' has been made by means of comparisons of the hybrid orbital force constants of $CH3SiH3,CH3GeH3$ and $CH3SnH3$. Empirical relationships have been formulated which permit the transfer of force constants between the molecules of this series using the C-H and X-H bond lengths as the only parameters. Some preliminary results indicate that these empirical relationships can be extended to include molecules not in the $CH3XH3$ series.