In the native amorphous organic thin film, and with analogy to the solvatochromic effect in solution, a solid state host with higher polarity can be expected to stabilise the CT state and red-shift the emission energy. However, a further complication for OLEDs is thay unlike the solution phase, the amorphous nature of the host material can produce permanent local electric fields and restrict the reorientation of the emitter. Our understanding of the complex nature of solid state solvation effects in OLEDs could be significantly enhanced by atomistic modelling.