A chemical interpretation of vibrationally induced barriers to hindered internal rotation

The preferred conformation of isotopically substituted ethyl radicals is determined largely by the contribution from the zero-point energy. Here the muonium is classed as an isotope of hydrogen. An independent oscillator model is proposed which enables the total zero-point energy to be partitioned into atomic contributions. This gives rise to a simple expression which predicts the preferred conformation and the height of the barrier to internal rotation. The parameters in this expression are interpreted in chemical terms.