First high-resolution analysis of the v15, v12, v5, v10 and v2 bands of oxirane

Fourier transform spectra of oxirane (ethylene oxide, c-C2H4O) have been recorded in the 730-1560 cm(-1) (6.4-13.7 gm) spectral region using a Bruker IFS125HR spectrometer at a resolution of 0.0019 cm(-1). A total of six vibration bands, v(15), v(12), V-5, v(3), v(10) and v(2), have been observed and analyzed. The corresponding upper state ro-vibrational levels were fit using Hamiltonian matrices accounting for various interactions. Satisfactory fits were obtained using the following polyads (15(1),12(1),5(1)) and (10(1),2(1)) of interacting states. As a result, an accurate and extended set of Hamiltonian constants were obtained. The following band centers were derived: v(0) (v(15)) = 808.13518(60) cm(-1), v(0) (v(12)) = 822.27955(37) cm(-1), v(0) (v(5)) = 876.72592(15), v(0) (v(3)) = 1270.37032(10) cm(-1), v(0) ( v(10)) = 1471.35580(50) cm(-1) and v(0) (v(2)) = 1497.83309(15) cm(-1) where the uncertainties are one standard deviation. (C) 2011 Elsevier Inc. All rights reserved.