The Millimeter-Wave Rotational Spectrum of CF3CCH in the Excited Vibrational State v10 = 2

The millimeter-wave rotational spectrum of CF3CN in the excited vibrational state v8=2

“…These spectra, like the CF 3 CCH spectra in v 10 = 2 state [9], are complex, with a superposition of three series for each J 00 corresponding to ' = 0 and ' = ± 2 with k' > 0 or k < 0. The first task is therefore to identify the quantum numbers k and ' associated with each absorption line in the spectrum.…”

“…It is clear that ' = 0 series has lower energy compared with other two series since X '' > 0. The ' = +2 and À2 series have the same energy at k = 0, and it can be seen that the positive series is displaced to lower energy and the negative series to higher energy [9].…”

“…For producing the initial prediction list, the parameters from the v 8 = 1 state [4,12] such as A, B, D J , D Jk , and q þ t were used, extrapolated as was done before for CF 3 CCH [9].…”

“…Hence, Table 1 The results of refinement of observed frequencies for CF 3 This has been termed vibrational '-resonance [9] to distinguish it from accidental resonances which can occur between energy levels not separated by the vibrational term X '' .…”

“…The present experimental work was carried with the same spectrometer used for the work presented earlier [9][10][11]. The experimental conditions were the same as those established for the study of the first excited states v 7 = 1, v 8 = 1, and v 4 = 1 [12].…”