Ergebnisse und Probleme am Schwingungsspektrum des Naphtalins
The question of the structure of naphthalene is one that has occupied chemists for many decades. Kekulé's models explain most of the chemical evidence. For a discussion of the fundamental vibrations of naphthalene it is very important to know the spectrum of naphthalene-d1 and naphthalene-d8. These substances have been synthetized and their Raman- and Infrared-spectra have been measured. It is presumed that the shifts in the region of [Delta]v 1585 and 1625 are due to the system of the double bonds. If the substituents are less electronegative, the shifts 1625 rise to [Delta]v 1630-1640 for instance by paraffinic and olefinic substitution. In this case not all C--C bonds probably are equivalent, but the 1,2-C--C bonds are more ethylenic.