Optical constants and vibrational analysis of ethylbenzene between 4000 and 450 cm21 at 25 8C

The optical constants (real and imaginary refractive indices), molar absorption coefficients and imaginary molar polarizabilities of liquid ethylbenzene between 4000 and 450 cm21 at 25 8C are reported for the first time. With the aid of ab initio calculations and previous literature gas phase assignments the liquid phase fundamentals are assigned. In addition, the barrier to rotation of the ethyl group is studied via ab initio calculations. The shallow local minima found in a previous study are examined and shown to be due to constrains placed on the geometry during the potential energy surface scan. q 2003 Elsevier B.V. All rights reserved.