Besides the possibility to distinguish different analogous amines, with similar chemicophysical properties, the methods reveal a technique to tune the optical properties of this material over almost the whole visible spectrum. Eventually, one can expect, that other compounds would enable a different blue-(or red-) shift of the optical properties, as well as, an irreversible incorporation in the material of the chosen element, such as boron, sulfur and so forth, making this material a very interesting platform for vapor sensing.