Fourier Transform Emission Spectra of the (000)–(000) Band of the λ4051.6 Band of C₃

Laser excitation spectrum of C3 in the region 26000–30700cm−1

“…When the 0 0 0-0 0 0 band of the 4050 Å system was found in spectra of the diffuse interstellar medium, [10] it was noticed [11] that the perturbations had resulted in a mis-assignment of the astrophysically-important R(0) line at 24676.7 cm À1 . This was confirmed by cavity ring-down spectra [30] of jet-cooled C 3 , and new Fourier transform emission spectra [31]. Some additional lines that were found in the cavity ring-down spectra have been assigned in a more detailed fluorescence study [32].…”

“…[4,11,[30][31][32] In part this is because we only observe lines with the lowest J values and at medium resolution. With higher resolution and warmer spectra, Tokaryk and Chomiak [28] have found small perturbations with shifts and splittings of up to about 0.3 cm À1 in several of the low-lying vibrational levels.…”

“…Analysis of theà 1 P u state [4,15,16,19,[25][26][27][28][29][30][31][32] is complicated by the overlapping of many of the bands, the irregularity of the vibrational structure caused by the orbital angular momentum and the presence of rotational perturbations. When the 0 0 0-0 0 0 band of the 4050 Å system was found in spectra of the diffuse interstellar medium, [10] it was noticed [11] that the perturbations had resulted in a mis-assignment of the astrophysically-important R(0) line at 24676.7 cm À1 .…”

The 4051 Å Comet Band of 13C3

“…A number of laboratory studies have been performed over the past half century to comprehensively understand the A − X electronic system. It was confirmed that the lower J levels in the upper A 1 Π u state of 12 C 3 are perturbed and some of the unassigned rotational lines observed by McCall et al (2003) were found to be due to transitions into two long-lived perturbing states (Zhang et al 2005, Tanabashi et al 2005. Previous spectroscopic studies on C 3 have focused on the main 12 C 3 isotopologue.…”

Division Xii/Commission 14/Working Group on Molecular Data

“…Shi et al (2010) have obtained spectroscopic parameters in the isotopologues of CN through ab initio calculations. Moreover, experimental work on bands in the A 1 Π u − X 1 Σ + g system of C 3 has appeared (McCall et al 2003;Tanabashi et al 2005;Zhang et al 2005;Chen et al 2010Chen et al , 2011. Perturbations have been seen in many of these bands.…”