Molecular structure and properties of CH3BeF and CH3MgF

The molecules methylberyllium fluoride and methylmagnesium fluoride have been studied using a priori electronic structure theory. Self-consistent-field wavefunctions have been computed over a double zeta basis set of contracted gaussian functions. The geometrical structure of each molecule has been predicted assuming the three heavy atoms are collinear. For CH₃ BeF, the predicted C-Be and Be-F distances are 1.70 and 1.40 Å. For CH₃MgF, the analogous bond distances are 2.08 Å and 1.78 Å. A number of molecular properties have been predicted including dipole moments, which are 1.75 and 2.38 debye for CH₃BeF and CH₃MgF.