This one should have a large Stokes shift. Photons emitted by the solute should not be reabsorbed by the solvent molecules. This condition is respected a priori because the solute emission spectrum is far from the solvent absorption spectrum. However, impurities dissolved in the solvent could modify its absorption spectrum and thend reduce the scintillator attenuation length. For example the quenching effect of the dissolved oxygen is a well known problem.
Commercial solvent have usually a non-satisfying purity.
So we tried to purify them with the help of the Chemistry Department. In this section, we will describe our purification prodcedure and the obtained results.