TY - JOUR
T1 - The CH stretching first overtone triad of ketene
AU - Strickler, Brent
AU - Nemes, Laszló
AU - Gruebele, Martin
N1 - Funding Information:
This work was supported by NSF Grant CHE-9986670 and a University Scholarship (MG), as well as the Hungarian Scientific Research Foundation (OTKA) under contract number T038422 (LN). We would like to acknowledge the use of program WANG written by Luckhaus and Quack (Department of Physical Chemistry, ETH Zürich), and we also thank Professor T. Miller and Dr. C. Carter for use of and assistance with the FTIR spectrometer at the Ohio State Spectroscopy Center.
PY - 2003/6
Y1 - 2003/6
N2 - We have observed and analyzed the first overtone triad of the v1 and v7 CH stretching modes of ketene in the range of 60006300 cm-1. The Ka = 0 components of all three bands could be assigned based on missing Q-branches and combination differences, allowing an unambiguous determination of the rotationless band origins for the 2v1, v1 + v7, and 2v7 bands. In addition, the Ka = 1, 2, and 3 subbranches as well as some higher Ka stacks were assigned for all three bands. The 2v7 band suffers from the most serious Coriolis perturbations, while at least some subbranches of the other bands could be fitted together. The anharmonic coupling structure perturbing the CH stretching overtones is discussed in terms of a quartic anharmonic force field derived from eight pair GVB/RCI calculations. Finally, an assignment of the Ka - 1 and Ka = 3 subbands of the 2v2 CO stretching overtone is also presented, together with an estimate of the rotationless band origin. A coincidence of several subbands prevented the unambiguous assignment of the Ka = 0 stack in this case.
AB - We have observed and analyzed the first overtone triad of the v1 and v7 CH stretching modes of ketene in the range of 60006300 cm-1. The Ka = 0 components of all three bands could be assigned based on missing Q-branches and combination differences, allowing an unambiguous determination of the rotationless band origins for the 2v1, v1 + v7, and 2v7 bands. In addition, the Ka = 1, 2, and 3 subbranches as well as some higher Ka stacks were assigned for all three bands. The 2v7 band suffers from the most serious Coriolis perturbations, while at least some subbranches of the other bands could be fitted together. The anharmonic coupling structure perturbing the CH stretching overtones is discussed in terms of a quartic anharmonic force field derived from eight pair GVB/RCI calculations. Finally, an assignment of the Ka - 1 and Ka = 3 subbands of the 2v2 CO stretching overtone is also presented, together with an estimate of the rotationless band origin. A coincidence of several subbands prevented the unambiguous assignment of the Ka = 0 stack in this case.
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U2 - 10.1016/S0022-2852(03)00092-4
DO - 10.1016/S0022-2852(03)00092-4
M3 - Article
AN - SCOPUS:0038051140
SN - 0022-2852
VL - 219
SP - 335
EP - 341
JO - Journal of Molecular Spectroscopy
JF - Journal of Molecular Spectroscopy
IS - 2
ER -