The millimetre-wave rotational spectrum of phenylacetylene

Broadband rotational spectroscopy of acrylonitrile: Vibrational energies from perturbations

“…(4) and (5) of Ref. [15]) to near ± 1 GHz Coriolis contributions to the rotational constants A 11 and A 15 . This near symmetric distribution of the values of the A rotational constants for the two excited states around that for the ground state, as well similar behaviour of other K dependent constants, like D JK and D K , have already been noted in [6].…”

“…The distinguishing feature between the various implementations was the type and the number of frequency multipliers generating the radiation, as illustrated by the multiplication factors listed in Table 1. Some measurements were also made in direct generation with a BWO-based spectrometer [14,15]. The final result is that the spectrum has been covered by means of a relatively small number of broadband segments, spanning a total of 1170 GHz of the spectrum, and including continuous coverage of the 182-640 GHz region.…”

Comprehensive analysis of the rotational spectrum of 2,2-dichloropropane

“…The mm-wave rotational spectrum was recorded with the broadband millimetre-wave spectrometer in Warsaw described in [4,5]. The spectrometer employs a combination of backwardwave oscillator (BWO) and cascaded multiplication sources, and measurements were on a static sample contained in a 3.5 m absorption cell at a pressure of 5-10 mTorr.…”

“…The polyad fits deliver deperturbed values of rotational constants, while in the effective single state fits (and in the CFOUR anharmonic calculation) such changes include the contributions from the Coriolis coupling. Correction for such contributions has been discussed in [5]. Perturbation increments to vibrational changes in, say, the rotational constant B for two coupled vibrational states v1 and v2 such that E v2 > E v1 can be expressed as…”

Rotation-vibration interactions in the spectra of polycyclic aromatic hydrocarbons: Quinoline as a test-case species

“…As the analysis progressed, the spectral coverage has been extended to several specific regions predicted to contain highly perturbed lines. A 222-238 GHz segment and multiple smaller windows at frequencies ranging from 282 to 298 GHz were thus recorded by using a backward-wave oscillator based millimeter-wave (mm-wave) spectrometer in Warsaw, 29,30 providing an estimated frequency accuracy of 30 kHz.…”