2 A and 3 2 A states. For the SOC 2 2 A and 3 2 A states of 87 Rb the largest negative shifts are for interaction with the ethene coat, as found for the non-SOC states. A similar trend is found for the transition energies of the SOC states of 87 Rb, when interacting with the coat molecules, where the 4 2 A state undergoes a blue shift and the 2 2 A and 3 2 A states shift to the red as the magnitude of the electric field increases. For each system at large 87 Rb-coat-molecule separation, R, the SOC 2 2 A state lies lower in energy (by ∼0.02 eV) than the SOC 3 2 A and 4 2 A states, where the latter two states are very close in energy.