Infrared Optical Constants and Computational Studies of Neat Liquid -Butylethylether

Abstract

Aliphatic ethers are of interest to researchers due to their wide application in the fuel, chemical, and pharmaceutical industry. In this paper we studied vibrational properties of neat liquidn-butylethylether (NBEE), including the determination of complex refractive index in the NIR and MIR range (11700–560 cm−1). The high absorption of neat liquid in the MIR range required the use of thin-film transmission recordings. The spectra analysis was based on conformational analysis and anharmonic calculations on B2PLYP/N07D level of theory. Final band assignments procedure was based on potential energy distributions. The theoretical investigation revealed that although 26 conformers of NBEE can be expected to exist in the liquid phase at 298 K, only few of them are essential for the forming of the spectrum. This study is important for the proper understanding of vibrational properties of other aliphatic ethers.