Sub-Doppler supersonic jet spectra of the coupled 6a¹₀and 6b¹₀vibronic bands of the S₁(¹B_2u) ← S₀(¹A_1g) transition in monodeuterobenzene and their rovibrational analysis

Abstract

We report the rotationally resolved spectra of C6HsD obtained in a supersonic seeded jet by Doppler free UV laser spectroscop~ with an effective resolution of about ff0045 cm -1. The coupled 6a~ and 6b0 vibronic transitions are analysed in terms of their spectroscopic constants (~0 = 38 634.2429 cm -~ for 1 1 1 6a0 and u0 =38637.1792cm-for 6b0) and the Coriolis coupling constant (~ = 0"095 85cm -1, obtained by constraining the C rotational constants to be equal for 6a 1 and 6b 1. Simulations of the spectra result in rotational temperatures of about 2 K. The polarizations of the two transitions could be determined unambiguously as well as the approximate ratio of the transition moments.

High resolution rovibrational spectroscopy of pyrimidine: Analysis of the B1 modes ν10b and ν4 and B2 mode ν6b

“…For the molecular symmetry group MS 4 (ab) corresponds to the permutation of the equivalent parts of the molecule and the upper right index of the symmetry species indicates parity (+ or À) [57][58][59][60]. Table 3 Measurement parameters for the region 600-1000 cm À1 of the infrared spectrum of pyrimidine …”

“…One mode (m 6b ) is expected to be of B 2 species, an in-plane mode with y-polarization. Table 1 The symmetry species for the normal modes of benzene [56], pyridine [39] and pyrimidine [41] according to Wilson's notation [55,56] For the sake of clarity, Table 2 shows the C 2v character table in relation to the S Ã 2 molecular symmetry group (MS 4 [57][58][59][60]), giving the relevant species, as well as the related parity (+ or À as exponent to the S Ã 2 symmetry species), the components of the electric dipole moment vector l in the molecule fixed axis system, the components of the rotational angular momentum J and the reduction n Cv of the vibrational species in C 2v for pyrimidine. The overall electric dipole rovibronic selection rule is:…”

Synchrotron-based highest resolution FTIR spectroscopy of chlorobenzene

“…1 (left, as in the I l representation). For the molecular symmetry group MS4 (ab) corresponds to the permutation of the equivalent parts of the molecule and the upper right index of the symmetry species indicates parity (þ or À) [26][27][28][29]. The symbols have their conventional meaning [1,30], g is the nuclear spin statistical weight for the corresponding rovibronic symmetry.…”

“…The character table for C 2v symmetry with the nuclear spin statistical weights is provided in Table 2. As discussed in [29] (for the background see [12,48,26]) the four protons and carbon nuclei exchanged in the permutation ðabÞ correspond with appropriate numbering to ðabÞ ¼ ð26Þð35Þð2 0 6 0 Þð3 0 5 0 Þ. The total Pauli-allowed species are A þ and A À (nurovibronic).…”

Spectroscopic study on deuterated benzenes. II. High-resolution laser spectroscopy and rotational structure in the S1 state

“…The rotational structures of C 6 H 6 and C 6 D 6 have been completely analyzed by Sieber et al 6 and Okruss et al 7 by high-resolution laser spectroscopy. As for the partially substituted isotopomer, there has been no report other than the work on C 6 H 5 D by Riedle et al 8 C 6 H 6 is a planar regular hexagon (D 6h ) and possesses 10 types of degenerate vibrations. 9,10 Although the S 1 1 B 2u ← S 0 1 A 1g transition is forbidden, the vibronic bands are observed by intensity-borrowing from other electronic states.…”