Full three-body primitive semiclassical treatment of [Formula Presented]

Primitive semiclassical quantization of H[Formula Presented] and D[Formula Presented] without the restriction of the separation of electronic and nuclear motions, reveals the existence of a small (10%) classical contribution to the one-electron chemical bond. It is found that in the electronic ground state the electron is exchanged classically between the two nuclei and that this exchange is correlated with the molecular vibration.