Quasiline absorption and fluorescence spectra of two single-bond conformers of trans-2-naphthylethylenes and their aza analogs

We report on the identification of the quasiline spectral systems of the nonplanar s conformers of trans-1-(2-naphthyl)arylethylenes embedded in n-alkane matrices at around 4 K. Taken together with the previously observed planar s conformers, we now obtain complete parallelism between the s conformers detected in n-alkane polycrystalline matrices at 4 K and the s conformers whose existence was previously inferred in fluid and glassy solutions on the basis of spectral and time-resolved studies