Substituent effects on circular dichroism of α-phenylethylamines
Abstract
The effect of para-substitution on the circular dichroism of α-phenylethylamine in different solvents, at room and at low temperature, has been studied. An analysis of various data and the different sensitivity of the 1∠b and 1∠a bands to changes in the pH led to the conclusion that the optical activity of the two bands is caused by different mechanisms.
A vibronic analysis of the 1∠b band which emphasises the role of non-totally symmetric vibrations is given.