HIGH-RESOLUTION ELECTRONIC SPECTROSCOPY OF MOLECULAR CONFORMERS - METHYL-3-AMINOBENZOIC AND ETHYL-3-AMINOBENZOIC ACID-ESTERS

Rotationally resolved fluorescence excitation spectra of the S-1 <-- S -0 origin bands of two conformers of methyl-3-aminobenzoate and four c onformers of ethyl-3-aminobenzoate have been obtained. Analyses of the se spectra yield the rotational constants of each conformer in the two electronic states and the polarizations of all six bands in the inert ial reference frame. Comparison of the results for the different confo rmers leads to an unambiguous assignment of specific bands to specific conformers and to an improved understanding of the factors that influ ence the S-1 <-- S-0 transition moment alignments in these and other s ubstituted aromatic molecules.