SUBSTITUENT EFFECTS .1. METHYL-DERIVATIVES

The structures of 35 monosubstituted methanes were calculated with the 6-31G⋆ basis set. Bent C-H bonds were found in most cases. The bond path angles for the H-C-X bonds were found to correlate with the electronegativity of X. The electron populations for each of the atoms were determined by direct integration of 6-31G⋆⋆ wave functions calculated at the 6-31G⋆ geometries. The populations also were correlated with the electronegativity of the substituents. The changes in population result from a combination of a charge shift toward the more electronegative atom in a bond and a movement of the bond critical point toward the less electronegative atom. The relative importance of these two terms was estimated. © 1990, American Chemical Society. All rights reserved.