High‐resolution stimulated Raman spectroscopy and analysis of the ν₁/ν₅ (C–H) stretching dyad of C₂H₄

Abstract

The high‐resolution stimulated Raman spectra of the ν1/ν5 C–H stretching bands of C2H4 have been recorded and analyzed by means of the tensorial formalism developed in Dijon for X2Y4 asymmetric‐top molecules. A total of 689 lines (428 for ν5 and 261 for ν1) were assigned and fitted as a dyad including Coriolis coupling constants. We obtained a global root mean square deviation of 4.39 × 10− 3 cm− 1 (4.61 × 10− 3 cm− 1 for ν1, 4.25 × 10− 3 cm− 1 for ν5). The nearby 2ν2 band, extrapolated from ν2, was included in the analysis. However, no interaction parameter involving it could be fitted. The analysis is quite satisfactory, although some parts of ν5 are not very well reproduced, probably indicating some yet unidentified resonances. This region is indeed quite dense, with many interacting dark states that cannot be included at present. Copyright © 2012 John Wiley & Sons, Ltd.

Frequency and Zero-Point Vibrational Energy Scale Factors for Double-Hybrid Density Functionals (and Other Selected Methods): Can Anharmonic Force Fields Be Avoided?

“…The compiled experimental fundamentals can be found in the Supporting Information. For the diatomics Cl 2 , ClF, CO, CS, S 2 , HCl, HF, N 2 , SiO, and SO, the data were taken from Huber and Herzberg, while detailed source references are as follows: C 2 H 2 , , C 2 H 4 , − CH 3 OH, H 2 CS, , CH 4 , ClCN, , CO 2 , H 2 CO, − H 2 O, H 2 S, , HCN, HOCl, N 2 O, NH 3 , − OCS, PH 3 , , SO 2 , CS 2 , BH 3 , and CCl 2 …”

Recent advances in linear and nonlinear Raman spectroscopy. Part VIII

“…Their analysis is quite satisfactory, although some parts of ν 5 are not very well reproduced, probably indicating some yet unidentified resonances. [141] Ballandras et al used highresolution stimulated Raman spectroscopy to analyze the ν 2 and ν 3 bands of C 2 H 4 . They obtained a global root mean square deviation of approximately 10 À3 cm À1 .…”

“…Aouididi and coworkers employed high‐resolution stimulated Raman spectroscopy for the analysis of the ν 1 /ν 5 (C–H) stretching dyad of C 2 H 4 . Their analysis is quite satisfactory, although some parts of ν 5 are not very well reproduced, probably indicating some yet unidentified resonances . Ballandras et al .…”

High‐resolution stimulated Raman spectroscopy and analysis of line positions and assignments for the ν2 and ν3 bands of 13C2H4

“…The most recent analysis of high‐resolution stimulated Raman spectroscopy of the ν 2 and ν 3 bands of 12 C 2 H 4 , and of the ν 1 / ν 5 (C–H) stretching dyad of 12 C 2 H 4 were carried out using the tensorial formalism developed in Dijon for X 2 Y 4 asymmetric top molecules and rely on spectroscopic information measured by the quasi continuous‐wave (cw) stimulated Raman spectrometer at IEM‐CSIC in Madrid.…”