alpha-Nitronyl nitroxide radicals have been widely used for obtaining molecular magnetic materials. We report two characteristics of this radicals that are important in order to interpret their bulk magnetic properties in the solid state. On one hand, we describe the modification of the spin density distribution in the radical molecule caused by different chemical surroundings and by different substituents using the Linear Solvation Energy Relationship multiparametric approximation. On the other hand, we report the self-assembly of some hydroxylated alpha-nitronyl nitroxides in solution. The supramolecular aggregates, formed in solution, are found to be very similar than those present in the crystal structures. This fact allows to establish clear magneto-structural correlations that facilitate the interpretation of solid state magnetic properties.