Przeglądanie według Temat "Rotational analysis"

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The 1 – v’’ bands progression of the B2Σ+ - X2Σ+ system of 12C17O+.
(Elsevier (Journal of Molecular Spectroscopy), 2006-08-30) Szajna, Wojciech; Kępa, Ryszard; Hakalla, Rafał; Zachwieja, Mirosław
The B2Σ+ → X2Σ+ (0-1, 2, 3, 4 progression) electronic transition of 12C17O+ was first observed and analyzed by Szajna and Kȩpa [Spectrochim. Acta A 65 (2006) 1014-1020]. We have now extended our previous studies. The use of high resolution conventional spectroscopic techniques has allowed first rotational analysis of the 1-2, 1-3, 1-4 and 1-5 bands of the first negative system in the 37,000-43,000 cm-1 spectral region. Approximately 500 transition wavenumbers were measured with an estimated accuracy of 0.005 cm-1. The present data were combined with the previous measurements to yield an improved set of molecular constants for the B2Σ+(v′ = 0, 1) and X2Σ+(v″ = 1, 2, 3, 4, 5). The v′ = 1 and v″ = 5 vibrational levels were observed for the first time and the main molecular constants are (in cm-1, one standard deviation in parentheses). {A table is presented}. The principal equilibrium molecular constants for the B2Σ+ and X2Σ+ states have also been derived and the vibrational terms values for the ground and excited states have been calculated. © 2006 Elsevier Inc.
The A2Δ–X2Π band system of the CD radical
(Elsevier (Journal of Molecular Spectroscopy), 2012-05) Zachwieja, Mirosław; Szajna, Wojciech; Hakalla, Rafał
The A 2Δ-X 2Π, Δv = 0 sequence of the CD radical was observed in the 22 800-24 000 cm -1 spectral region using a conventional spectroscopic technique. The CD molecules were formed and excited in a stainless steel hollow-cathode lamp with two anodes and filled with a mixture of He buffer gas and CD 4. The emission from the discharge was observed with a plane-grating spectrograph and recorded using a photomultiplier tube. The observed lines were assigned to the 0-0, 1-1, 2-2, and 3-3 bands. In total, 1189 transition wavenumbers were precisely measured, with an estimated accuracy of 0.003 cm -1, and rotationally analyzed. In the final global fit, the present data were combined with available high-resolution measurements of the vibration-rotation transitions [Morino et al., J. Mol. Spectrosc. 174 (1995) 123-131] and pure rotational transitions [Brown and Evenson, J. Mol. Spectrosc. 136 (1989) 68-85; Halfen et al., Astrophys. J. 687 (2008) 731-736]. This procedure enabled the extraction of molecular constants for the A 2Δ and X 2Π states of CD. The equilibrium parameters were compared with the calculations performed using the Born-Oppenheimer approximation, and a slight difference was observed in some cases due to the partial breakdown of the B-O approximation. The electronic isotopic shift, Δν e, for the A-X transition was determined to be 32.105cm -1, and the shift independent of the nuclear mass coefficient, ΔU=64.762(38)cm -1, was also calculated. © 2012 Elsevier Inc.
The B2Σ+ - X2Σ+ transition of 12C17O+: the 2 – v'' progression.
(Taylor&Francis Group (Spectroscopy Letters), 2007) Szajna, Wojciech; Kępa, Ryszard; Hakalla, Rafał; Zachwieja, Mirosław
Three new bands of the B2Σ+-X2Σ+ system of 12C17O+ have been investigated using conventional spectroscopic techniques. The spectra were observed in a graphite hollow-cathode lamp by discharging molecular oxygen (enriched in about 45% of the 17O2 isotope) under 1.0 Torr pressure. The rotational analysis of the 2-4, 2-5, and 2-6 bands was performed with the effective Hamiltonian of Brown (Brown et al., J. Mol. Spectrosc. 1979; 74: 294-318). Molecular constants were derived from a merge calculation, including both the current wavenumbers and the spectroscopic data published by the authors previously. The principal equilibrium constants for the ground state of 12C17O+ are ωe=2185.9658(84), ωexe = 14.7674(11), Be=1.927001(38), αe=1.8236(22) × 10-2, γe=-0.331(28) × 10-4, De=6.041(12) × 10-6, βe=0.100(31) × 10-7 cm-1, and the equilibrium constants for the excited state are σe=45876.499(15), ωe=1712. 201(12), ωexe=27.3528(39), Be=1.754109(35), αe=2.8706(57) × 10-2, γe = -1.15(19) × 10-4, De=7.491(20) × 10-6, βe=2.13(12) × 10-7, γe = 2.0953(97) × 10-2, and αγe=-9.46(59) × 10-4 cm-1, respectively. Rydberg-Klein-Rees potential energy curves were constructed for the B2Σ+ and X2Σ+ states of this molecule, and Franck-Condon factors were calculated for the vibrational bands of the B-X system. Copyright © Taylor & Francis Group, LLC.